Big Brother Instinct



"Big brothers...you know why they're born first? To protect the little ones that come after them!"

- Ichigo Kurosaki, Bleach

One very common way to establish that a male character is a Nice Guy (even if the niceness is hidden under a gruff exterior) is to give him an instinctive desire to be a big brother to smaller, younger, weaker or female characters. These other characters may be truly younger siblings, or they may be completely unrelated, or even older, and the tendency for males to act as their protector is the Big Brother Instinct. Female examples exist, though in a smaller proportion.

The Big Brother Instinct serves to explain why fan attraction to Moe tropes and devices can be an emotional, rather than sexual, response. There seems to be something inherently comforting to an awkward male about being looked up to by a younger girl for support. Therefore Moe can be wish fulfillment about taking a "big brother role" instead of about being a Love Interest (although that version is common too).

If both characters are male, the older (or in the case of twins, the physically stronger) brother will usually act as the younger/smaller brother's protector, to the point of treating him like a child, even when the younger brother is fully capable of protecting himself. This behavior can come across as loving and nurturing or as condescending and smothering. If the older brother goes to extreme, morally questionable lengths for the sake of the younger sibling, then they are a Knight Templar Big Brother. And while Good Feels Good, it could feel too good.

Compare Cool Big Sis, Mama Bear, Papa Wolf and Promotion to Parent. Contrast Big Brother Bully.

Has nothing to do with the TV show Big Brother. The Nineteen Eighty-Four meaning of "Big Brother" is covered under Big Brother Is Watching.

Anime and Manga
"Kamina: Don't call me Kamina, call me bro!"
 * Brock from Pokémon is pretty much this trope. He takes care of nine siblings when his parents hit the road.
 * Fist of the North Star: Kenshiro is this trope. While usually brooding and serious, one of the few things that makes him genuinely crack a smile is being around Bat and Lin. Hurt or threaten Bat and Lin and, well, You Are Already Dead.
 * Narumi of Karakuri Circus, in spades. Masaru begins to mimic him.
 * Guy Shishioh in GaoGaiGar. Just hurt or threaten Mamoru in front of him and start counting how long it takes for him to wipe the floor with you. Mamoru even calls him "Big Bro".
 * Code Geass gives us the trope picture and HUGE examples.
 * Lelouch is the king of this trope. Has anyone else on this page started a war for their little sister? Then there's his reaction to her possibly falling in love with Rai, the main character in the Dating Sim Lost Colors, though that one is Played for Laughs.
 * He also intended to set Nunnally up with his best friend Suzaku, who cares about her almost as much as Lelouch does.
 * Cornelia similarly has this going on for Euphemia. Prior to their exile, she also treated Lelouch and Nunnally this way,.
 * The Chinese officer Li Xingke has one of these for his lady of liege, the considerably younger Empress Tianzi.
 * Kyon from Suzumiya Haruhi. He set himself up as a Stoic in the novels for ages. Being the Unreliable Narrator that he is, we can all see that he's Not So Stoic. Still, he was just annoyed when Haruhi grabs him by the collar and slams the back of his head onto her table. Even then, it was mainly because she disrupted the class.
 * During the filming of their amateur, plotless movie, Haruhi gets Mikuru to drink alcohol, trying to get a certain effect out of her. He almost attacks Haruhi. Let us repeat. He almost attacks somebody who he knows is a reality-warper.
 * In the seventh book, Mikuru is kidnapped. Kyon flies into a rage (for the second time in the novels), and immediately calls up Haruhi for help, forgetting she still doesn't know she's a Reality Warper. He claims it was a failed practical joke to cover up.
 * In the tenth novel after  Kyon completely loses it and runs out to track down Kuyo Suou and personally make her fix it. To reiterate, he actually went out of his way to get into a confrontation with an alien interface who he knows has god-like powers. Naturally, he's totally out-classed but it's the thought that counts.
 * Mai Tokiha from My-HiME has a Big Sister Instinct towards her kid brother Takumi.
 * Shattered Angels: Kyoshiro and Kazuya. It's a bad one too; people die. Quite a few people, actually.
 * A much straighter example would be Tsubasa and Souma in Kannazuki no Miko: the entire conflict between them stems from Tsubasa's desire to protect Souma as effectively as possible, which unfortunately involves pulling him to The Dark Side and killing his love interest. Also, Tsubasa killed their father who beaten up Souma when were very young, which is why they were separated.
 * Kaon for Tarlotte.
 * D.Gray-man:
 * Mad Scientist Komui Lee is fiercely overprotective of his younger sister and only relative, Lenalee. The only way to wake the fiercely lazy Komui up is by saying "Your sister's getting married!" Since SHE is the one of the duo with the monster-killing super powers, he's got a lot to worry about. His obsession with his sister is mildly creepy.
 * Link even weaponizes this at one point, threatening Allen with telling Komui that he's alone in a sealed room with Lenalee if he doesn't unlock a door that's shutting the good inspector out.
 * Allen uses it to blackmail, saying he'll tell Komui about the pictures of Lenalee he has in his office.
 * In Cardcaptor Sakura, Yukito jokes that, despite Touya's teasing of Sakura, he has a protective instinct when it counts, something he indeed acts out, secretly aware of her Magical Girl alter life.
 * Possibly played straight or inverted (depending on whether he is oldest or not) Syaoran acts as this towards his cousin Meiling in the anime adaption. His treatment of Sakura arguably evolves somewhat into this at first (even if it ultimately becomes a somewhat different relation by the end of the series).
 * Subverted brutally in Saint Seiya, when Ikki beats the stuffing out of his younger brother. He eventually turns around, un-subverting the trope.
 * And he keeps on un-subverting it for the rest of the 100+ episodes, to the point where the Reluctant Warrior younger brother getting hurt in a fight became a sure-fire way to summon Ikki from his lone wolf brooding cave, screaming bloody murder and mind rape (in anything not drawn straight from the original manga).
 * Haré+Guu: Haré has a big brother instinct towards his frequently irresponsible mother. Guu teases him about his "Mazacon" (mother complex) from time to time.
 * Averted and subverted (naturally) in Revolutionary Girl Utena with Nanami and her brother Touga. Whereas Nanami's big brother complex is extreme to the point that she is in love with him, Touga couldn't care less about her well being. Enter Mitsuru, a fourth grader, who she uses as a whipping boy after he saves her. She sees him as her servant, and he is fond of her-in fact, Utena and the others suspect that Mitsuru has a crush on Nanami, but he reveals that he wants to protect her like a brother would, unlike Touga. During his Black Rose duel episode, this is mentioned in the form of him being sexually and emotionally confused. It's shown that his interactions with the teenage Nanami piqued his curiosity about being grown-up, so he reads books about "adult"-related topics.
 * Subverted again (and to a twisted level) with
 * Subverted (again) and then played straight with Miki and Kozue. While he does protect his sister and genuinely care for her (unlike Touga), he projects the image of his sister when she was younger onto Anthy, whereas because of a childhood incident, Kozue becomes something of an Attention Whore to annoy Miki (and there is possibly another reason). Miki is oblivious of her reasoning until Kozue's Black Rose duel. Compared to the rest of the student council (and the other duelists for that matter), though, Miki is more level-headed, and he realizes his mistake early enough to both move on and become the resident Nice Guy among the cast.
 * Played straight in Mawaru Penguindrum with the Takakura sublings. The whole plot is based on Shouma and Kanba trying to save Himari's life.
 * Mahou Sensei Negima:
 * Ayaka claims to have an overdone big sister instinct which her friends and the viewer apparently grossly misunderstand. Asuna has a more genuine version, that occasionally threatens to misunderstand itself.
 * Kaede also feels this way towards both Negi and Kotaro: A Love Chart produced in-universe shows that her romantic feelings for Negi are fairly low, but her maternal score is off the scale, surpassing the quite motherly Chizuru (10), matching Evangeline (12), and topped only by Asuna (15). This doesn't always show mostly because of her laid-back personality.
 * Love Hina: Keitaro takes on a big brother role towards Shinobu early on, which does result in her developing an ongoing crush for him.
 * Yu-Gi-Oh!:
 * Seto Kaiba is a total jerk to the main characters but will go to outrageous lengths to save his brother Mokuba. Mokuba is kidnapped a lot, though. Probably because Kaiba is such a jerk.
 * Jounouchi Katsuya is very protective of his little sister Shizuka. When she sends him a video message telling him about how she is slowly going blind, he sneaks into the Duelist Kingdom tournament that Yuugi was invited to so he could win the prize money and pay for an operation to save her eyesight. He also becomes extremely protective over her when Honda and Otogi begin flirting with her and competing openly for her attention.
 * Minor character Espa Roba seems to have been Promoted to Parent in the past and is this to his four younger brothers. Even after Jonouchi caught him cheating, the revelation made it hard to stay mad at him, since Jonouchi could relate.
 * Ishizu is completely willing to die if it means saving her little brother, Marik, from his psychotic Split Personality.
 * Marik's adoptive brother Rashid was this towards towards him as well, another example of a foe whom Jonouchi could relate to for this reason.
 * Ichigo Mashimaro: Nobue is a female version, serving the protective role towards her 12 year old sister and her friends. She also feels a near sensual pleasure watching them act cute, making her an easy victim of their manipulations.
 * Inuyasha:
 * For a short while, Kagura seemed to develop a big sister instinct toward Kohaku, until she
 * Sesshoumaru has a complex, evolving relationship with his brother Inuyasha . Prior to the story's start, it appears Sesshoumaru bullied and ignored Inuyasha for not being pure-blooded Youkai, and his first few story arcs revolve around Sesshoumaru's efforts to obtain the Cool Sword that their father left for Inuyasha - by murdering Inuyasha if necessary. As the story progresses and Sesshoumaru's character develops, however, Sesshoumaru's motives become more ambiguous, taking on more of a flavor of "I Was Just Passing Through" and "Nobody kills my brother but me." The conflict between them is eventually resolved
 * Although the exact nature of Sesshoumaru's protective instincts can be debated in one-or-two cases (notably Jaken ), his instinct to protect expands throughout the series more-or-less as follows: Jaken (who really doesn't feel the love most of the time), Rin, Inuyasha, Kagome,  Sesshoumaru's development is finally lampshaded in the final chapter
 * Digimon: This is a continuous theme throughout nearly every season. Some have this problem with actual siblings, and others tend to apply it to their Digimon.
 * In the first season there was Yamato towards his brother and the youngest Digidestined Takeru. Hikari spends a good bit of Digimon Adventure 02 trying to live up to her big brother Taichi's reputation as a leader. And let's not even get started on Ken Ichijoji, who's desire to live up to his dead brother's memory in his parents eyes was the start of his whole descent into darkness.
 * Taichi is overly protective of Hikari before 02 though. The best example, episode 48, when Hikari falls ill and Taichi borders on hysterics the entire time. Then we find out why he's so over-protective (Taichi took Hikari outside to play while she had pneumonia, and she almost died.)
 * The twist of the knife is that Hikari never blamed Taichi for it. Quite the opposite: Hikari apologized to Taichi for not being able to kick the ball straight, which only made him feel worse and want to protect her "kind heart" even more!
 * Jyou/Joe shows a bit of this towards Iori/Cody in 02. Though he did have some inklings of this to Takeru/TK already in the first series.
 * In Digimon Frontier, pretty much everyone was like this towards Tomoki/Tommy, but he seemed to especially look up to (and be stuck with) Takuya and Junpei/JP.
 * Kouji and Kouichi, of course. It went both ways, but especially Kouji towards Kouichi.
 * Daisuke/Davis seemed to behave like this towards his Digimon partner, Veemon.
 * In Digimon Savers, Masaru/Marcus and his Agumon were like that (Masaru even admitted that he thought of Agumon like his brother). Masaru also was very protective of his little sister.
 * Ikuto/Keenan and his Digimon partner, Falcomon, were raised to believe they were brothers, and treat each other accordingly.
 * Then there's Touma/Thomas, who has a little sister whom he acts quite the same towards as Tai.
 * Another example from Digimon Adventure—Sora acts extremely protective of her partner Biyomon, eventually spurring her Digivolution into Garudamon.
 * In Digimon Tamers, Jenrya was rather overprotective of his youngest sister Shiuchon. This behavior turned out to be a bad influence on her when she got her own partner.
 * In The Prince of Tennis, if you mistreat Yuuta Fuji in almost any way, get ready to face his older brother Shuusuke's rage. Just watch and compare Fuji's matches with Jiroh Akutagawa and Ryoma Echizen with the one against Hajime Mizuki . No wonder Fujicest is among the most popular yaoi pairings in the fandom. Also, lampshaded in the anime when Fuji aids a girl with similar problems towards her older sister.
 * Sister Princess is basically nothing but this. To an unhealthy extreme, in fact.
 * Kyo Kara Maoh!: Shori has a certain obsession with protecting his younger brother at all costs.
 * Gwendal is very protective of Wolfram, and at times Conrad, though it is hard to see at first due to his stern nature. Conrad is very protective of Wolfram and Yuuri. Though Yuuri is the king, so he should be protective, he is Yuuri's godfather, and thus often acts like an older brother/father figure.
 * Conrad seems to have had a genuine 'Big Brother Complex' over Wolfram when he was small. The transformative episode when, at a guess, Conrad was about forty (looked twelve) and Wolfram was about fifteen (looked three) in which Gwendal sorted out his relationship with Dan Hiri, Conrad lost his father, and Wolfram found out his favorite awesome brother was half human appears to have started the trend that terminated in his behavior at the beginning of the show: calling Gwendal as 'Aniue' and Conrad as 'Weller,' his surname. And once Wolfram rejected him, Conrad eventually moved on to obsess over someone else. With a period of cynicism in the middle, out of which Gunter knocked him by kicking his ass.
 * Will go even more on a tangent to say that Gunter and Conrad's abortive fight in the Dai Shimaron arc was awesome.
 * Night Head Genesis: Naoto obsesses over Naoya, his kid brother who has empathic powers that render him mostly helpless
 * In True Tears Jun displays this kind of attitude toward Noe, his younger sister. Hiromi even comments on it. In fact,
 * The Daughter of Twenty Faces: The relationship between Ken and Chiko becomes this very quickly. It's so blatant that several characters, including Ken himself, hang a lampshade on the fact.
 * Fullmetal Alchemist: The main plot revolves around Ed scouring the earth for a way to restore his younger brother Al's body to normal. On the other hand, considering Al is inhabiting an animated suit of armor much larger than Ed, there's a quite unusual dynamic going on there. Especially considering how Ed reacts to anyone calling him short.
 * Ed sacrificed his arm to keep his brothers soul in existence. If that's not Big Brother Instinct, what is?
 * The Elrics both have this dynamic towards each other. Edward was more than once willing to die for Al (until he realized that if he died no one else would be able to put Al back to normal) -- and Al did NOT approve of Edward's plan to let himself killed by Scar so latter one would leave Al alone. Later in the first anime Al . And at the ultimate end of the first anime, in the movie, they spend much time, stress and tears to find each other again, succeed, —that's FMA for you...
 * The first anime and one of the novels also feature the Tringham brothers Russell and Fletcher. Russell is very protective of his brother, though it takes him a while to realize that otherwise he's been neglecting him. He gets better.
 * Scar's older brother.
 * In Bleach, one of Ichigo's biggest Berserk Buttons is an older brother harming his younger sister. He gave us the page quote.
 * Though he's still nothing compared to Orihime's brother, Sora. He's really possessive of his sister, even after death. He is shown to have become extremely jealous that Orihime likes Ichigo, and to put it in his words, "I wanted you to pray for me, because only during the time you were praying for me your heart was mine."
 * And in his back story, he ran away with a three year old Orihime from their abusive parents as soon as he turned eighteen, and proceeded to raise her on his own before being killed in an accident.
 * In the Hell Verse movie, when Yuzu dies, Ichigo's Berserk Button is broken in the On position until Renji stops him.
 * And in the Hueco Mundo arc, Ichigo comes across Nel, and they seem to form kind of a Badass and Child Duo.
 * And although it took a while, previously very-Aloof Big Brother Byakuya Kuchiki has now demonstrated a willingness to kick huge amounts of ass in defense of his sister Rukia.
 * Gundam 00: Mix this with Blood Knight and Ax Crazy, and you have Michael Trinity.
 * Mix this with Subordinate Excuse and Extreme Doormat, and you have
 * Clannad: A female-female example. Harass Ryou, and her sister Kyou will throw a huge book straight to your face and kick you while dazed.
 * Youhei Sunohara is the series' Butt Monkey most of the time, but mess with his sister Mei and he'll do an Offscreen Teleportation to kick your ass.
 * Tomoya also seems to have this going for him, despite not having any siblings. Whenever Mei calls him Onii-chan, he becomes overly excited and is willing to do whatever she wishes from him.
 * Gundam X: Subverted with Shagia and Olba Frost. Not only the siblings in question are villains and brothers (instead of brother and sister), but the one who blindly adores and fiercely protects his sibling is Olba, the younger of the duo.
 * Axis Powers Hetalia:
 * Switzerland is like this with his Token Loli sister Liechtenstein.
 * South Italy hates his younger brother North Italy's ally Germany because he thinks he's not good for his sibling (and since both Germany and Romano are male Tsunderes.)
 * According to Word of God, Norway acts similarly towards Iceland. Confirmed in a strip, where Norway tries to make Iceland call him "Oniichan" (an honorific that usually little kids use towards their older brothers) and strangles Denmark with his own tie when he cracks jokes about it.
 * In the Baltic area, the usually calm Estonia can be reduced into a nervous wreck in regards to his younger brother of sorts, Latvia, and with good reason. LATVIAAAAAA, indeed.
 * England also acted as an older brother figure to America, in his own way. The Revolutionary War thus broke his heart, and he still seems to have a soft spot for him (not that he'd ever show it, of course).
 * Challengers: Souichi is fiercely protective of his younger brother Tomoe (as well as homophobic) and will not hesitate to pummel Kurokawa when he shows an overt romantic interest in Tomoe.
 * Narutaru: Female-female example:
 * Trigun: Knives is this way about Vash, but it's a really dark version, since Knives thinks that Vash's idealism and pacifism aren't doing him any good, and need to be beaten out of him.
 * Incidentally, they're twins, and no one was there to see them born. When Vash explains who Knives is in the anime, at least, he uses the absolutely-ambiguous word 'kyoudai,' 'sibling,' which carries neither gender nor age, because Japanese doesn't have a birth-order-ambiguous version of 'brother.' (The same word is applied to all their 'sister' bulb-plants in the manga. Confusingly, it's supposed to be an English-speaking planet.) Knives basically appointed himself big brother after becoming evil and deciding Vash was a wimp.
 * Anime Knives always had Big Brother tendencies, but in the manga back when they were still cute Knives was the sensitive one, and Vash actually looked after him slightly more than the reverse.
 * I.e., pointing out that even if Knives is right and "there's no real difference between people's hearts and ours," it's going to take a lot of work, and comforting him when Knives starts crying after William Conrad, the first human they ever met besides Rem, accepted them.
 * Anime Vash interpreted Rem's last words, "Knives o--" [mouth forming three inaudible syllables] as "Take care of Knives," though the meaning of this appears to have shifted in his head to mean 'beat the shit out of Knives' by the time they meet in July.
 * Basilisk has Saemon Kisaragi and his younger sister, Okoi. Even when Okoi is quite able to defend herself, all of the Koga Manjidani know that upsetting her is a bad idea not just because she'll punch them immediately, but because the ruthless Saemon will be NOT amused as well.
 * Peacemaker Kurogane: Tatsunosuke is overly protective of his younger brother Tetsunosuke. The other characters tease them both about this.
 * Fairy Tail: Mirajane and Elfman are a weird example of this: Elfman (technically the younger brother) is extremely protective of Mira, probably due to, flying into a rage when she's in danger and threatening anyone who flirts with her. However, Mira is also deeply protective of him, and rightly so, considering that.
 * In Fruits Basket, Momiji's little sister, unaware of their relationship, solicits this, asking Momiji if he will be like a big brother to her.
 * Haru acts this way towards Kisa, including running through the rain to find her after she runs away and giving her the strawberries from his cake.
 * Higurashi no Naku Koro ni: It is implied that Satoshi was like this toward Satoko before his disappearance. A year later, Keiichi and Shion take up the position . Satoko actually starts calling them "Nii-Nii" and "Nee-Nee".
 * In one of the PlayStation 2 arcs, implied to be the way that Minagoroshi-hen could have gone,.
 * In Umineko no Naku Koro ni, Battler behaves this way both towards his actual younger sister, Ange, and to his little cousin Maria. He bonds with Maria early on in most of the arcs despite not having seen her in six years, and is very protective of Ange. After Ange, Battler snaps out of his funk and goes up several levels in badass and sets his mind back on track to defeating Beatrice and making it back home to her.
 * In Kashimashi: Girl Meets Girl, Tomari's crush on her formerly male best friend, Hazumu, comes out of her sisterly instinct to protect her. In the anime that protective side gets a bit less attention, though, and her feelings for Hazumu are presented more as a straightforward crush.
 * Vocaloid- although technically all the canon Vocaloids are supposed to be siblings- has Len Kagamine, who in vids is protective or over-protective of his sister, Rin, although Rin is supposed to be the older one.
 * In Getter Robo: Armageddon, Go immediately adopts this attitude towards Kei upon encountering her. It's eventually revealed that the reason for this is that . It's complicated.
 * Subverted in Death Note where Villain Protagonist Light Yagami in an early Motive Rant claims that part of the reason he wants to make a better world is to protect innocents like his little sister, Sayu, and he has a Pet the Dog moment early on helping her with her homework, but
 * Early on, he suggests that he'd have to kill her if she found out about him being Kira.
 * In Naruto, Shame he went about it in the most fucked up, traumatizing, and ultimately futile way possible.
 * Actually, according to the story we're told, his goal was to make Sasuke a hero of Konoha. The only way he'd be allowed to continue to live there after
 * Kankuro is a more positive example. Although he and Gaara have a poor relationship at first, the brothers become much closer after Gaara's Heel Face Turn, and Kankuro willingly risks his life to go after Gaara when the latter is kidnapped by Sasori and Deidara - although it doesn't end well for either of them - and stands up for Gaara when an elder badmouths him. Considering how terrified he was of Gaara in Part 1 (and with good reason!) this is quite a change and shows just how much Gaara's change in circumstances has affected the family dynamic.
 * Darker than Black: There is a reason Hei goes completely nuts when his Dead Disappeared Little Sister is brought up.  In the second season,
 * Of the few redeeming traits of Ryo Narushima in Shamo is his protectiveness towards his younger sister.
 * Fushigi Yuugi has Tamahome (towards his siblings, and initially, Miaka, after she told him she missed her actual brother Keisuke) and Tasuki (towards Chiriko).
 * Hayate the Combat Butler has a semi-standard version of this, and a strange pseudo-subverted version.
 * Hayate sees himself as Nagi's protector/big brother and it's possible that he tries to exemplify it for all of the girls around him, possibly because of his own big brother's influence.
 * It even extends to Wataru and possibly Kazuki. There's only one other character he won't protect, even going so far as to try and kill. Continually.
 * The Katsura sisters have a warped version. Yukiji protected her sister when their parents left them with a large debt, taking care of it herself and shielding Hinagiku from the 'evil' side of society. Now she looks up to Hinagiku as the more capable one, having dealt with their abandonment and still having a loving outlook on life, while Hinagiku herself protects Yukiji and is hinted to help her with funding issues from time-to-time, while still punishing her for 'get-rich-quick' schemes she attempts.
 * Game X Rush has this for his younger brother Memori, particularly when Memori was a younger crybaby.
 * In Akira, Kaneda feels this way towards Tetsuo, because they were friends since childhood. Even though he teases him, he still feels the need to protect him and shows affection for him as a younger brother.
 * Seto from Heavens Will has one of the weirdest Big Brother Complexes ever.
 * Baccano! has two examples: Maiza, who serves as a sort of Big Brother Mentor to the young gangster Firo (who is supposedly somewhat similar to his biological younger brother, who ), and Dallas, an unrepentant Jerkass whose one redeeming trait is his kindness towards his little sister. The three Gandor brothers are also very protective of one another.
 * Baskerville has this towards Mingchao in Et Cetera. Partially because he's dealing with
 * In One Piece, Portgas D. Ace is very protective of his little brother Luffy. This goes from
 * Also Zoro to Chopper, who keep an eye out for the little guy and becomes upset when anyone hurts Chopper.
 * Kaiser Ryo for his younger brother Sho in Yu-Gi-Oh! GX, at least at first. Saiou for his sister Mizuchi in Season 4. A strange case is Fubuki for Asuka, in that he both attempts to get her to date other guys and manages to convey Brother-Sister Incest undertones simultaneously. Regardless, he does care for her as a sister, but usually it's her that ends up saving him.
 * In Magical Girl Lyrical Nanoha, Cinque of the Numbers is quite protective of her younger sisters, staying behind to fight Subaru and getting badly injured in the process to allow Nove and Wendi to escape. Even though her crimes are more severe than the other Numbers and she does not expect to ever be completely free, she decides to atone for them and cooperate with the investigation so she can help her younger sisters.
 * In Yakitate!! Japan Kawachi does this to Azuma, due to Azuma having to worry about Kawachi. When Kawachi lost the battle with Kanmuri in the Pantasia Newcomer's Battle
 * Katekyo Hitman Reborn. Any person willing to injure Kyoko or Tsuna, answers to Ryohei's fists and Tsuna's family.
 * Durarara!!'s Shizuo Heiwajima is rather protective of his little brother Kasuka (aka Teen Idol Yuuhei Hanejima). The mere act of namedropping Kasuka is enough to make him suspicious of your intentions, while insulting him or attempting to poke into his personal life results in an instant Unstoppable Rage. In the Light Novels, he eventually goes on to develop another Big Brother Instinct towards a young runaway Yakuza Princess.
 * In Binbou Shimai Monogatari, Kyou has this toward her younger sister Asu, which is justified since they live by themselves and she has taken on a parental role. Since Kyou is still very much a child herself this doesn't always come easy for her, but luckily Asu compensates by often acting very mature for her age.
 * Fujimiya Ran in Weiss Kreuz goes so far as to take his little sister Aya's name after she's rendered comatose; he becomes an assassin primarily to pay her hospital bills, and not only is he fiercely devoted to her welfare, he displays knee-jerk protectiveness toward anyone who reminds him of her. This is most evident in his interaction with Identical Stranger Tomoe Sakura, but it also flavors his behavior toward several other young women and makes him a Big Brother Mentor toward Sena in Gluhen and Yuki in Side B.
 * Toki from Code Breaker is part of the Code Breaker group in order to keep his sister Nenene safe (though she's apparently older than him, and doesn't remember who he is).
 * Ozma Lee from Macross Frontier is extremely protective of his little sister Ranka, even though she's adopted. He even manages to break the pineapple cake curse because he promised not to die so long as Ranka still needed him. Also played straight with.
 * Shannon Casull plays this trope straight in Scrapped Princess In fact most of his best moments this trope.
 * Grumpy, cynical Sanzo in Saiyuki is this towards Goku, despite voicing his annoyance about Goku constantly. Hurting Goku is a whole different matter.
 * Demon prince Kougaji cares deeply about his half-sister Lirin and would do anything for her.
 * Gojyo's half-brother is this, despite being on opposite sides with Gojyo and feels tremendous guilt for not being able to protect him from the abuse of his mother. His extreme protectiveness over Kougaji is motivated by how he couldn't keep his biological half-brother safe and a way to gain redemption for not being able to. His complete psychological breakdown when he thinks he couldn't keep Kougaji safe reflects this.
 * In Tengen Toppa Gurren Lagann, Kamina has this towards Simon. Expressed elegantly with this line:
 * Gojyo's half-brother is this, despite being on opposite sides with Gojyo and feels tremendous guilt for not being able to protect him from the abuse of his mother. His extreme protectiveness over Kougaji is motivated by how he couldn't keep his biological half-brother safe and a way to gain redemption for not being able to. His complete psychological breakdown when he thinks he couldn't keep Kougaji safe reflects this.
 * In Tengen Toppa Gurren Lagann, Kamina has this towards Simon. Expressed elegantly with this line:

"Lin: Don't worry... stay right where you are, I'm coming to get you! You're gonna be fine, I won't let him hurt you. Lin: No Face! If you put even one scratch on that girl, you're in big trouble!"
 * Inverted in Rave Master where younger brother Haru is fiercely protective of his older sister Cattleya. He had once beaten up a guy who broke her heart and would have done it again when he ran into the guy later on in the series.
 * Soukou no Strain. After Ralph Werec has his Freak-Out in the backstory (brought about by ) he views the only survivor of the aliens as a substitute little sister, and is more than willing to do anything to avenge her race, and I mean anything, to the point of wanting to kill his actual younger sister when she stands in his way.
 * In the Wild Series, Kiri has a strong caring instinct for his little brother, Mao. Granted, it doesn't stop him from immediately trying to kill Mao when Mao loses control of his beast side, but he probably considered that a favour.
 * In Yu-Gi-Oh! 5D's Crow shows this attitude towards; Leo, Luna, Yusei, Akiza, Jack and even his younger siblings. To the point where he'd become the Idiot Hero
 * Guache of Tegami Bachi has this for his little sister, Sylvette.
 * Maho from Wandering Son may be a bully to her little brother, but don't you dare mess with him.
 * Kanba Takakura from Mawaru Penguindrum has such a strong one towards his and Shoma's little sister Himari—that it borders on Brother-Sister Incest.
 * Ouran High School Host Club plays with this with a few of its members, most notably in the episode where Nekozawa's little sister Kirimi wanders up to the high school, putting both Nekozawa and Tamaki in the big-brother spotlight in turn.
 * In addition, Hunny and Mori have this relationship with their brothers Yasuchika and Satoshi (manga-only), though Hunny's way of showing it is admittedly...weird, to the point that the anime completely overlooked it.
 * And Hikaru and Kaoru, being twins with a lot of identity issues to work out, go back and forth on treating each other this way. Usually Kaoru takes up this role while guiding Hikaru to maturity, but when he gets too self-sacrificing for his own good Hikaru will press his big-brother advantage to set him straight.
 * Lin from Spirited Away becomes quite protective over protagonist Chihiro over the course of the film.


 * In Saint Beast, Kira attacks anyone who so much as talks to his brother Maya initially. Considering the Fantastic Racism they are usually subject to, this is somewhat justified, but it also scares off potential friends.
 * Natsuki from Tsuritama over his little sister Sakura, to the degree that she's one of the very few things that can crack through his grumpy demeanor and get him to smile. Haru saying to Sakura that Natsuki'll be teaching him and Yuki how to fish is the only reason Natsuki agrees to do it, just to keep her from feeling let down.
 * In Persona Trinity Soul, Ryou used to be like this 10 years ago.After their family reunited he turned out to be .His younger brother Shin also have this toward their youngest brother Jun.Shin is really worried about Jun,he really worried when Jun came back home 30 minutes late than usual,including .But it turns out.

Comic Books

 * Quicksilver is protective to the point of jealousy when it comes to his sister the Scarlet Witch. This is taken further in Ultimate Marvel.
 * The Mighty Thor: Thor treated Loki this way in early flashbacks to their childhood; however, it only aggravated Loki's already raging inferiority complex, putting him on the path to villainy.
 * However, after Loki accidentally (YMMV) brought about the near-total destruction of Asgard, was killed in a last-ditch heroic sacrifice to save what was left(that may have been part Xanatos Gambit) and reincarnated as a kid with only his childhood memories, he appreciates this protection a lot, since the only reason most people in Asgard haven't killed him yet is because they know Thor would go on a Roaring Rampage of Revenge on them and the city if Loki is harmed.
 * Kid Loki seems to be similarly protective of Thor. During the "Fear Itself" event, he engages in dark dealings and all to save Thor from being killed by The Serpent.
 * X-Men:
 * Has this with Wolverine being a Big Brother Mentor to the younger heroines, including Kitty Pryde, Jubilee and his Opposite Gender Clone X-23.
 * Though they can find it hard to get along, Cyclops still tends to treat Havok this way, insisting on carrying his coma-ridden brother into the X-Mansion despite the presence of a wheelchair and being so protective and interfering that they're mistaken for a couple in an issue of X-Factor.
 * Batman: Between Nightwing and (adopted) little brother Tim Drake - one issue had Tim believed to have been murdered by the Joker when a mass Arkham escape was in progress. Nightwing takes it hard.
 * Catwoman tends to be a female version of this whenever she acquires a female tag-along who's too old for this to be considered Mama Bear.
 * Not to mention Dick and Batman's biological son Damian, who eventually softens up to Dick, though he probably wouldn't say it out loud to Dick.
 * Occurs with (intentionally invoked) Unfortunate Implications in American Born Chinese: When the Chinese boy Jin starts to date his classmate Amelia Harris, an Anglo friend strongly urges Jin to stop, saying he wants her to "make good choices."
 * In a Star Wars: Tales series, mercenary Darca Nyl comes across a mentally handicapped GIANT of a man and his petite sister fleeing from pursuers. One night, while camping, the girl is set upon by a huge and vicious predator. Darca knows that he can't reach them in time to save her, when the man leaps at the beast with a large rock in his hands. Several minutes later, the creature has long since stopped moving and he keeps smashing at it with the rock.
 * Rose and Thorn, an odd DC Comics heroine, is a truly unique example. Vigilante Anti-Hero Thorn sees herself as a protector to her meek, emotionally vulnerable sister Rose, but Thorn is not Rose's sister, she is a second personality of Rose, who inadvertently created Thorn out of anguish from her father's murder. Thorn, to her point of view, is protecting Rose while avenging their father.

Fan Works
""You took my little brother, tied him up, pumped him full of heroin, and left him to die in this shit hole. Now I ask you: do you think I have the slightest bit of remorse about cutting you open and letting your guts decorate the floor?""
 * The Firefly fanfic Forward has a very plausible version of this develop between Jayne and River, after
 * Uriel Dolheb Sohryu in the Neon Genesis Evangelion fanfic Nobody Dies has this towards Asuka Langley Sohryu, given that she's his adopted sister and he feels compelled to protect her and make her happy, even if he has absolutely no idea how to do it beyond giving Shinji the If You Ever Do Anything to Hurt Her... speech. His Big Brother Instinct also extends to Asuka's half-sister Mari Illustrious Makinami, to the point where her attempts to flirt with him fly completely over his head.
 * Do not threaten Kanae in front of Kyon in Kyon: Big Damn Hero. Do not try and kill Kyon once he's done teaching you why you shouldn't attack Kanae. She may not be his little sister, but he treats her like one.
 * In Axis Powers Hetalia's Fanon, it's a known fact that America is protective of his twin brother Canada. Sometimes, he's portrayed as an over-protective brother whenever another nation is interested in Canada.
 * There was this one story (based on Vocaloid's "Servant of Evil" series), where Russia had killed Canada, mistaking him for America. Bad move, as America promptly declares war on Russia.
 * It goes the same way with Russia and his two sisters Ukraine and Belarus. There was this one story where Ukraine had mysteriously vanished, Russia believing that America was the one doing it  grabbed him by the throat and for all measures, was perfectly willing to rip America's head if it would bring his sister back.
 * In the Batman fic The Choice of Family, it was inverted when Tim and Damian angrily called out Jason for putting Dick in danger and having him end up at the hospital. But it was played straight in the sequel Antidote for the Poison where Jason was furious when he found out Tim was injected with a dangerous amount of heroin by some drug dealers. When he cornered said drug dealer, who knows what he might have done if Damian wasn't there.


 * Jason also openly acknowledges Tim and Damian as his younger brothers and brings Damian safely home after he and Damian go out to get the drug dealers.
 * An odd goblin example of this trope (though with the sister being the protective one) can be found in Travels Through Azeroth and Outland.
 * Raonar, the Guile Hero dwarven prince in Dragon Age: The Crown of Thorns, develops some advanced protective tendencies towards the dwarven commoner, Faren, as evident when the former finds the latter The resolution with the sloth demon can be seen as a partial subversion, however, because it's  himself who, ultimately,  before the protagonist
 * A female example in The Legend of Spyro: A New Dawn is Cynder towards Ember. Ember is slightly younger than her, but is very childish and naive. Despite the fact Ember has her characteristic crush on Spyro (though in this case, it's due to being to socially naive to realize Cynder and Spyro are mates), Cynder ends up having this mentality towards her, even describing her as being like "an annoying little sister" at one point. This makes hurting Ember in front of Cynder one of her Berserk Buttons, which Cyros finds out the hard way when she Cynder reacts violently.
 * Fanon often have Gaara and Kankuro of Naruto threatening Shikamaru in Shika/Tema Fanfics or any other fics that involve Temari getting hooked up with someone. They're technically little brothers as Temari is the eldest sibling.
 * It also doesn't help that Gaara is in fact the Kazekage, which means he has some authority over Temari. To which he abuses or at least attempts to abuse said authority.
 * In the Death Note fanfic Xanatos, Matt shows this toward Linda, most notably in chapter 3.
 * In Harry's New Home, the normally law-abiding Percy snapped when he found out someone tried to Crucio Ron.
 * In For Good, Buzz Lightyear has a very serious Berserk Button in his adopted little sis.
 * Quite a few ponies in Equestria Chronicles.

Film -- Animated

 * An American Tail: Fievel tries to ward off the Cossacks' cats for that reason.
 * Brother Bear: Kenai hates bears, and finds Koda REALLY annoying, but would still go through anything to protect him.
 * In Toy Story 3, Andy is this to his sister, Molly, despite their light bickerings. When she had trouble lifting a box, he immediately went to help her. And at the end,
 * Fly in Help! I'm a Fish, who's pretty caring when it comes to Stella, his little sister. Case in point: When it seems like searching for her in starfish-form in the ocean via boat is hopless, he doesn't hesistate to drink a potentially dangerous potion and dive in, in order to continue searching.
 * Disney's Robin Hood has the titular character acting this towards Skippy and the other children. After the Sherif takes Skippy's birthday present (a gold coin his family managed to save for him), Robin Hood comes in to cheer Skippy up and gives him a bow and arrow and his hat. Later on, when one of Skippy's sisters struggles to catch up with the escaping villagers from Prince John's castle, Robin Hood doubles back to get her.
 * In The Prince of Egypt, Rameses' first reaction to his little brother killing a man in front of multiple witnesses is to declare him innocent. When Moses returns after years of being gone he is ready to give his brother a high position and wipe away the crime. That didn't turn out.
 * From the same movie Aaron tries to protect Miriam when she approaches Moses before Moses knows of their relationship.

Film -- Live-Action
"Haru: I may not be the best Ninja... I may not be one with the universe... but I will tell you this... no-one messes with my brother!!"
 * The Blind Side:
 * He also will not tolerate anyone saying something derogatory about his adoptive little sister, Collins.
 * X-Men: For all Wolverine's (many many) flaws, Victor "Sabertooth" Creed really does love his little brother Jimmy, very very much.
 * Also, from the same movie, Kayla appears to be willing to do just about anything to keep her sister safe.
 * X-Men: First Class: Darwin develops this for the younger mutant recruits, especially when Shaw attacked the CIA base. Unfortunately,
 * Also Charles had this for Raven, being very concerned for hiding her appearance in public and telling her to her face that he didn't want anything to happen to her. However, his relationship with her deconstructs this phenomenon as it caused him to become overprotective to the point where he denied her the chance to embrace her true appearance and be proud of what she was, as well as caused him ignore her very obvious crush on him. This in turn made Raven turn to Erik Lehnsherr as a mentor/love interest and eventually join him in his cause against humanity.
 * Arguably, Erik developed this for Charles. He went out of his way to protect Charles during the Cuban Missile Crisis, even
 * Push: Nick and Cassie.
 * House of Wax: Nick posesses the instinct quite strongly, which makes his behavior towards his younger sister, Carly, look filled with Incest Subtext.
 * The City of Lost Children: One for Denree and Miette.
 * Star Wars: He's only the big brother by about six or seven minutes, tops, but Luke Skywalker definitely qualifies. He's all redeeming and peaceful and unflappable in the face of evil despite a million reasons not to be, but all bets are off when the Big Bad makes a totally impotent, hinted threat towards his sister. Suffice to say, he doesn't react well.
 * The Godfather's Sonny Corleone, in spades. He launches into one of the most epic No Holds Barred Beatdowns in film history against his brother-in-law after he finds his sister with a black eye..
 * Seen in West Side Story when Bernardo interferes in his sister Maria's budding romance with Tony. Double Subverted in that Tony is the only decent member of the Jets, genuinely in love with Maria and with good intentions... but then he ends up killing Bernardo in a fit of rage over the death of his friend.
 * Eomer to Eowyn in The Lord of the Rings. He was furious that Wormtongue was following his sister. For that matter, Eowyn didn't want Wormtongue anywhere near her either.
 * And let's not forget Tony Montana in Scarface. Just a tad bit too protective of his little sister Gina, even going as far as.
 * Peter Garret in Vertical Limit climbs up K2 to rescue his sister Annie
 * The titular character of Ginger Snaps is an interesting example - her protectiveness towards her younger sister is essentially, a snarky sense of humour aside, her only redeeming quality, and even that's pretty messed up. They have a suicide pact ("Out by sixteen or dead on the scene,") and her gradual case of lycanthropy worsens, However, Sam could be seen to have a genuinely alturistic Big Brother Instinct towards Brigitte, as he gives her an awful lot of help, carrying a fair amount of risk, with no benefit whatsoever to himself. Although some people interpret it as him having a romantic interest in her.
 * Becca from The Descent is very caring and protective towards her sweet little sister Sam, and to a lesser extent, the rest of the less-experienced caving group. Also, it's fairly subtle, but Beth displays Big Sister Instincts towards anyone in the group who needs it - she's constantly looking after the emotionally fragile (due to the death of her husband and child) Sarah, she gives her jacket to Holly after she breaks her leg and helps her stand and walk (along with Sam, The Medic) and she goes back to help Juno in the crawler fight, even though she doesn't like Juno much.
 * Aussie horror flick Black Water is actually rather sweet in spots due to it's use of this trope. Initially, we have both Grace and her boyfriend Adam towards Grace's shyer, more panicked sister Lee. However, Lee turns out to have one hell of a Little Sister Instinct herself. You see it emerging slowly throughout the film, but once Grace is injured, Lee is literally willing to face down crocodiles if it means she can get her sister out of there and to a hospital. Turns out she's just much braver for her sister's sake than she is for her own.
 * In Beverly Hills Ninja, Haru seems to be the worst martial artist in history, surviving to the film's climax mostly through dumb luck. However, at the climax, when his more competent brother-via-adoption Gobei is about to get his ass handed to him by enemy fighters:


 * And he proceeds to wipe the floor with the mooks to the tune of "Kung-Fu Fighting".

Literature

 * In the Belisarius Series it is exhibited by several characters. One Persian princess (who later marries the Roman Emperor), is vainly protected by his brother from Hun mercenaries under Roman pay after the Persian army is defeated (though she is rescued when the Roman general's bodyguard arrives). The best example of big brother instinct though is Rajiv Sanga. He is a nice polite teenage killing machine and is very protective of his siblings and to a lesser degree family servants and allies (though he will make concessions to Combat Pragmatism if he can't protect someone he wants to protect). Interestingly he extends that even to nominal enemies when he realizes that they were untrained sheep for the slaughter unless he intervenes to get them a chance to surrender.
 * John Steinbeck's Of Mice and Men has a western example of this trope in which George Milton, a Jerk with a Heart of Gold, cares for Lenny Small, a mentally retarded Gentle Giant.
 * In The Dresden Files:
 * Harry becomes this to Molly when . He also does it to his half-brother, despite the fact that is the older brother.
 * also has a brother instinct. He has followed Harry around town without Harry's knowledge, and in the past few books the only time hasn't come to Harry's aid was when the White Council was directly involved. And he is very protective of his little sister,.
 * Kincaid and The Archive have a similar relationship.
 * Chronicles of Narnia: Peter, especially if it's about Edmund.
 * The movie version of Prince Caspian portrays Susan falling in love with Caspian. Peter definitely seems to oppose Caspian in every matter, getting to the point where they almost battle each other. It's almost as if Peter is destined, from the beginning, to hate the guy and bash him, while his little sister is instantly swept off her feet by him.
 * Edmund develops this for Lucy, after his Heel Face Turn.
 * Peter has this pretty strongly toward Lucy as well. He vehemently rebukes Edmund for humiliating her in the beginning of the series, up to the point that he looks like he's about to deck his younger brother in the movie.
 * Dragonlance Chronicles: Critical to Raistlin Majere's backstory. He spent his youth under the overprotective influence of his twin brother, Caramon. While Caramon grew up tall, handsome, muscular, and a bit dense, Raistlin was intelligent, but sickly and alienated, with no friends but his brother. Seeking to prove his worth to his smothering "big brother" and the world at large, Raistlin seeks the power to topple Gods, and gets it. Deprived of a little brother to protect, Caramon falls into alcoholic depression.
 * Ron Weasley reveals this in Harry Potter and The Chamber of Secrets while nearly cursing Malfoy (with a broken wand that has already backfired once on him) for being mean to Ginny. Basically, the two best ways to get Ron angry are to insult either Ginny or Hermione.
 * Ron gets a bit of this from Percy after the Second Task in Goblet of Fire. Percy, who's supposed to be acting as an impartial judge give Harry full marks for rescuing Ron and hovers over Ron until Madam Pomfrey drags Ron off for treatment.
 * Eclipse Hunter: Devon falls under this trope very easily, and fills many different archetypes. He's willing to  if it means protecting Daren.
 * In The Thief Lord, Prosper's protectiveness of Bo is the main motivation behind his character. He runs away from his aunt with Bo to prevent their separation, joins a gang of urchins and even steals to make sure his brother is well fed and sheltered, and goes into a major Heroic BSOD when Bo is finally taken away.
 * The Darkest Powers series gives us Derek. He has a Big Brother Instinct that's Up to Eleven when it comes to his foster brother, Simon. Derek is also a werewolf. So on top of the fact that he is, personality-wise, very protective of Simon (and anyone else he cares about), he also has the wolf's "protect my pack" instinct to deal with. Assaulting one of his "pack" is his Berserk Button. Unfortunately for Derek, since he can't usually control his reaction when his brother is in danger no matter how much he's tried to coach himself, his supercharged Big Brother Instinct has led to at least one My God, What Have I Done? moment.
 * Chalet School: Len Maynard. Oh, Len Maynard. Practically ever since she is a baby, she is pigeonholed as the 'responsible one' and as the oldest Maynard child, she is often put in charge of the other Maynard children. She has a major one where Margot is concerned, protecting her from Jack's wrath and even lying to cover up for her in Triplets of the Chalet School after the bookend incident. Miss Annersley even calls her on it.
 * In Watership Down, Hazel is usually calm and collected, but god help you if you mistreat Fiver or Pipkin.
 * Kaladin from The Stormlight Archive develops one of these for every relatively (around 14) young male he comes across in the course of the story. This stems from his feelings of guilt over failing to protect his actual younger brother in the course of a minor border dispute between rival lords of his nation.
 * The Cal Leandros series gives us Niko, who loses his characteristic cool when someone so much as implies that his brother is a monster, and literally goes berserk with rage when he thinks Cal is dead. Cal is no better, going to extreme lengths to protect his brother.
 * Although Damon Salvatore of The Vampire Diaries likes to make his brother's life hell, he does go out of his way to save or protect Stefan.
 * Katniss Everdeen of The Hunger Games will go to any lengths to protect her younger sister Primrose, including volunteering for the titular Deadly Game in her sister's place, a seemingly suicidal gesture.
 * Prince Jonathan and his group of friends in Song of the Lioness developed this for the new page Alan. Even before Ralon started bullying Alanna, they regularly helped and kept an eye out for her. And when Ralon first beat up Alanna, Raoul pulled him aside and roughed him up as a warning. When Ralon later broke Alanna's arm in retaliation, they all thrashed him thoroughly. Despite continuing to harrass Alanna, Ralon didn't lay a hand on her again.
 * Alan and Nick Ryves in The Demon's Lexicon.
 * Lynn Flewelling is fond of using this in her Nightrunner books:
 * Before their Relationship Upgrade to the Official Couple level Seregil had this to Alec, though there had been subtones early on.
 * And both Alec and Seregil are always and at any time rather protective towards Beka (in Seregil's case it is also a rather paternal feeling; he states himself she's as close for a daughter to him as it will ever get.) - including being suspicious about her lover, checking him up, threatening him not to harm her... Beka is not impressed.
 * Tamir Triad: You better not insult Tobin when his squire/best friend Ki is around. (and in fact thanks to plot this brother-friendship later gets rather difficult)
 * An even creepier example might be the ghost Brother. Tobin's older twin who died after birth and turned into an angry spirit. After Tobin learned how to keep him in check Brother actually got extremely protective - despite the claims of some characters this troper never could shake the feeling that Brother DOES feel affection and brotherly love towards his sibling. Albeit in a twisted way.
 * In The Outsiders, everyone was this towards Johnny since his abusive parents could care less about him. Also, Ponyboy's two older brothers Sodapop and Darry, especially after their parents' death.
 * Brandon Stark was this for his sister Lyanna in the backstory to A Song of Ice and Fire. When Crown Prince Rhaegar Targaryen abducted and raped her, Brandon rode off to King's Landing with a few companions to kill Rhaegar and rescue his sister. It didn't go well....
 * In Ender's Game, the reason that Ender was willing to go to Battle School and join the International Fleet was to protect his sister Valentine, although he was actually her little brother.
 * In the In Death series, Roarke tends to harbor protective instincts toward Eve's female colleagues, though they're not particularly weak. This is probably due to his Dead Little Sister.
 * In The Voyage of the Jerle Shannara, Quentin Leah already has a pretty serious big brother complex towards his cousin Bek. Following his failure to save a girl he liked, this is magnified a thousand fold, and helps to fuel his change into a badass.
 * Bertie of Jeeves and Wooster tends to develop this easily. In one story he suddenly decided that he wanted a daughter for precisely this reason: "Something to look after, if you know what I mean."
 * Mr Darcy towards his younger sister Georgiana in Pride and Prejudice.

Live-Action TV
"Burt: Keep an eye on your brother. Finn: Way ahead of you."
 * Simon and Simon: Brothers Rick and A.J. both exhibit this trope. Although Rick is older, he and A.J. are both protective of each other, as shown in almost any episode.
 * iCarly Spencer in regards to Carly and Gibby to his little brother Guppy.
 * The Colbert Report: Stephen Colbert has admitted he sees Jon Stewart as something of an older brother figure in Real Life. It's one of the few Real Life traits that bleed through into the characters' lives, most recently in the Melee a Trois crossover with Conan O'Brien, which Stewart only got involved in because he was protecting Colbert.
 * Buffy the Vampire Slayer: Spike takes pains to keep Dawn from harm in a few episodes, when Buffy or the Scoobies are unavailable to do so.
 * The A-Team: Face and Murdock show this for each other quite a bit. Murdock is older than Face, but they both have their share of "big brother" moments when it comes to looking out for each other.
 * Also, B.A., towards both of them. He's allowed to verbally abuse them and threaten them with physical violence on a regular basis, but if anyone else tries it...
 * A little odd in his case, seeing as, when you do some figuring, B.A. may actually be younger than Murdock, and possibly younger than/the same age as Face. He's still protective of them. But he'll never admit that he likes either of them, especially not Murdock.
 * Angel: Played for laughs in an episode, when Angel and Doyle deliberately act in an over-protective fashion towards a prospective boyfriend of Cordelia's in order to mess with her.
 * Angel actually was a big brother, and his evil alter ego Angelus killed his little sister.
 * Everyone seems to get this really bad for Fred. Well, except for her love interests. They kinda got something worse...
 * Firefly is a show that brothers and sisters over the world can watch together and feel happy, warm feelings for each other.
 * Simon rescued his little sister River from a bad place, and is very protective of her. Very much so. The Tams have an Undying Loyalty to each other, they provide a lot of the best Crowning Moment of Heartwarming scenes and a number of Crowning Moments of Awesome.
 * Captain Mal Reynolds extends something like this to his entire crew, but particularly Kaylee, whom he even refers to as mei-mei or "little sister" a couple of times.
 * Inara is also very willing to play the Big Sister role. "Mei-mei" is most commonly used by her towards other (usually younger) female characters.
 * Everwood has a lot of that: Bright starts off being a bully in the pilot, but later on in the same episode it's revealed he cares a lot about his younger sister and her comatose boyfriend. That's also expanded throughout the first season, to the point that his friendship with Ephram stems from his desire to keep her sister happy (in real life, Bright's and Amy's actors actually dated). It could also be mentioned that Ephram was protective of Delia, and Dr Abbott also became sort of a father figure to his sister after their father died (even though they were both already adults).
 * Gossip Girl: Chuck and Serena with Eric (or is it Erick?), Dan with Jenny (especially on the pilot). Lily's siter also counts.
 * Jane Lynch's character in Glee: pure evil, except for her ill sister.
 * Finn has developed this for Kurt, especially since their parents got married. The exchange between him and Burt when  says it all:

"Emily: Screw protocol; Reid's in trouble."
 * Justin from Wizards of Waverly Place always fixes Alex's mistakes and saves her from impending doom. She even admits that she always expects him to do so.
 * Hence the complexity of their relationship. Complexity as in Cain and Abel, Slap Slap Kiss, some Foe Yay, Double Entendres, More Than Brotherly Love Signs and You Know Where I'm Going With This.
 * Or perhaps just a case of Relationship Writing Fumble and Getting Crap Past the Radar.
 * And a serious one due to the fact that the fans started asking the producers if Justin and Alex are going to end up together. It's Disney Channel, after all.
 * Brutally subverted in the Cold Case episode "Shuffle, Ball Change". The victim's brother was simultaneously protective and fond of his younger brother, yet he derided his ambitions to be a dancer and ultimately murdered him in a fit of jealous rage over his impending success (along with grief over his own failure as a wrestler).
 * Dean and Sam Winchester, of Supernatural. This is a show that's actually about being brothers. (The bromance being fashionable this decade.)
 * Dean Winchester is absolutely insane on this point. 'Take care of Sammy' has been his entire life motto. He dies for him, he sells his soul to Hell for him, he keeps going back for him no matter how screwed up things get between them and what Sam gets dragged into, he takes him back no matter what...and honestly the way the show is written, the latter two there seem to cost him more than the first. Especially seasons four and six, when Sam was slipping darkside and walking around without his soul, respectively.
 * Sam turns it back on Dean pretty hard, himself. Even in Season One he completely flew off the handle when Dean looked to die, and season three was all about saving Dean to him, and he pretty much lost his shit once Dean went to Hell.
 * And he overpowered Satan for Dean in the Season 5 finale. Sure it saved the world, but it wasn't the world he thought about. But he's actually four years younger, and Dean practically raised him.
 * The angel Castiel gets adopted as an unofficial third Winchester brother some time in Season 5. Because he is young to the world and they are young to being and lack power, the 'big brother' role swaps back and forth a lot, and sometimes Dean and Cas are both big-brothering one another in the same scene. Though Dean never turns the Sam-level obsessiveness on Cas.
 * The evil thing doing an overwrite of Dean's mind and body in 7.06 complained that he "doesn't have relationships, no, he has applications for sainthood," which is pretty much just that raging protectiveness and self-sacrifice is pretty much the only setting he has for people he cares about. Which isn't to say he can't be a raging dick to these same people, because he can, but Big Brother's Privilege.
 * Numb3rs: Don Eppes was always Charlie's protector and on the few occasions when criminals come after Charlie, Don becomes a Papa Wolf and decides that It's Personal . Don also shows concern that Charlie will be affected by the grim aspects of law enforcement and feels a little awkward accepting help that might conflict with Charlie's career as a professor.
 * Burn Notice: Michael Weston has this towards his little brother.
 * Bill Scully Jr. of The X-Files has a Big Brother Instinct for his youngest sister Dana, though he can be a jerk about it and doesn't always bother to get all the facts before lashing out at people he sees have "wronged" her...like Mulder. Poor Mulder.
 * In Criminal Minds Derek Morgan definitely acts like this towards Spencer Reid, especially if he's in danger/threatened with his life. "I'm gonna get this guy's head on a pike" says it all.
 * Derek's just the most obvious. All of the characters have this towards Reid. Emily in particular joins Morgan in this, with her Older Sister-like relationship with Reid. For evidence, just look at her taking a beating in "Minimal Loss" to save Reid from getting shot, and this line from "Amplification":

"Jaye: You don't screw with my family."
 * Heroes: Nathan Petrelli to his little (26-year-old) brother, Peter. Sometimes... When it comes down to it, it's clear that he loves his brother. (Of course: )
 * Peter towards Claire. Usually
 * Some fans see the relationship between Jack O'Neill and Daniel Jackson this way. Others have a slightly different opinion.
 * In Can You Hear My Heart, Joon Ha goes so far as to abandon his biological family to take care of a boy with a hearing disability.
 * We could be sure that Hassan from Over There was like this when Colonel Roye threatened him about his sister so he could tell him where the stingers are.
 * One from Power Rangers. Vida, the Pink Mystic Force Ranger, is already a pretty aggressive character. But threaten (or otherwise belittle) her sister Madison, and it doesn't matter whether you're an enemy or a colleague. Vida will tear you in half.
 * Inspector Lynley: Barbara Havers is a cranky, foul-mouthed junk food addict who can't seem to work well with anyone in the police force except her partner Thomas Lynley. On the other hand, she is incredibly good with children and will go to any lengths to protect them.
 * Bones: Booth and Brennan toward their psychologist, Sweets. His old mentor flat-out states in one episode that Sweets - raised in an abusive home, adopted by a loving older couple who then died when Sweets was in his late teens or early 20s - is subconsciously seeking to build a surrogate family with the pair.
 * There's also Booth and his younger brother Jared. Booth was willing to give up a massive RICO case which would have given him a promotion, a raise and a trip to Hawaii just to get Jared off on a drunk driving charge. He was also very dubious of Jared's love interest and actually did a background check on her.
 * Lois and Clark: The titular couple to Jimmy Olsen.
 * ER: Many of the older staff toward Carter, but particularly Greene and Benton - the latter to the point of being a Papa Wolf.
 * The Vampire Diaries: When the tomb vampires kidnap and torture Stefan, his brother Damon literally massacres every vampire in the house.
 * Prison Break: Linc toward Michael, and Michael - though the younger brother - to Linc.
 * In Wonderfalls, much though Jaye finds her family irritating, she has a very strong Little Sister Instinct. In one episode, after a guy punches her brother (played by the rather tall Lee Pace), Jaye (played by the decidedly smaller Caroline Dhavernas) manages to lay out the guy with a single punch.

"Because I worry about him. Constantly."
 * Warehouse13: Both Pete and Myka, towards Claudia. Just try watching "Breakdown," and not awwwing a little. For her part, in Claudia's introductory episode, she breaks right into the freaking Warehouse and kidnaps one of the main characters in order to force him to help her rescue her brother Joshua, who was zapped into an interdimensional space (and not, as initially thought, killed) twelve years prior.
 * Farscape: Crichton towards Chiana.
 * Leverage: Eliot is clearly starting to feel this way about Parker, although he doesn't like it and would never admit it. When a fake psychic caused her to break down in tears and run away, Elliot had to be restrained from killing the man. He also is this with Hardison, though they are quite hostile to each other
 * to Sherlock.


 * On Boy Meets World Eric shows this toward Cory intermittently, such as when he protect Cory from a bully.
 * Damon has this for Stefan on The Vampire Diaries, in a way.
 * In Merlin, Arthur and the rest of the knights seem to be developing this for Merlin during Season 4. All of them were horrified when Merlin nearly died saving Arthur from the Dorocha and then warmly welcomed him back when he recovered. Of course, this protectiveness is a little misplaced since he could easily take on all of them with his powers!
 * In Blue Bloods, Danny is this with both Erin and Jamie, but especially with Jamie, since his gut instinct in crisis situations seems to be making sure his "kid" is safe.
 * In Wishbone Sam see a team mate being picked on so she takes him under her wing and teaches him to play better.
 * In The Big Valley, Nick, Heath, and especially Jarrod are very protective towards Audra. There are good examples of this in first season episodes "The Midas Man" and "Last Train
 * NCIS: McGee to his sister. Abby to her brothers. Everyone to Abby.

Mythology and Religion

 * Apollo from Classical Mythology tricked his twin sister Artemis into killing Orion because he feared this was one guy she could give up her vow of chastity for.
 * To the great surprise of those who watched the movie Troy, Agamemnon in the original Classical Mythology has this in spades. Paris fucked with Menelaus, Agamemnon will make Troy burn
 * More "little sister instinct" for St. Angela Merici, who grieved when her older sister died without rites. Then she received a vision telling her that her sister was in heaven. In gratitude she devoted the rest of her life to religion and service to the poor. Ah....

Professional Wrestling

 * The Hardy brothers, Matt and Jeff. Matt as the older brother, both in story lines and Real Life, often plays this role. (When he's not this, he instead is the Jerkass.)
 * A group of GLOW villains kidnapped Little Fiji to lure her older sister Mountain Fiji out of the arena to ensure Mountain Fiji wouldn't get another victory.

Video Games

 * The Big Daddies and Little Sisters in BioShock are based directly on this trope. The Big Daddies are massive cyborgs that have been programmed to always watch over the Little Sisters and protect them at all costs, while the Little Sisters are conditioned to always stay close to a Big Daddy and rely on them for protection. Neither Big Daddies nor Little Sisters are agressive and attack on their own, but unfortunately you need the ADAM the Little Sisters extract from corpses with huge syringes, which they don't give up willingly. And when somebody touches a Little Sister her Big Daddy will fight to the death.
 * BioShock 2 goes even further and puts you in the role of a Big Daddy whose Little Sister was taken away and who had been dead for 10 years. When he is revived, the Little Sister Eleanor calls for his help to rescue her from her mother's imprisonment. For most of the game you put half of Rapture upside down and tear through hordes of splicers to get back to her and save her.
 * As a Big Daddy you also have the ability to adopt other Little Sisters and have them harvest ADAM for you. This leaves them vulnerable to attacks from splicers for about a minute during which you crush the skull of anyone who is trying to attack her.
 * The main character (whether male or female), Akihiko and Junpei serve as adopted big bros (and sis) to Ken in Persona 3. Akihiko's issues related to his Dead Little Sister mean that he also has some protective big brother impulses towards Fuuka and the female protagonist. Shinjiro is similarly protective towards Fuuka and constantly laments what happened in Ken's past. In Persona 4, the main character acts this way towards Nanako, whcih leads to many moments that make you go aaaww. In short, Persona loves this trope.
 * Galaxy Angel gameverse: Noa, although she's got some plans of her own.
 * Kana: Little Sister: This trope is played to the max. The player assumes the role of a boy who cares for his terminally ill younger sister.
 * Prototype: Mess with Dana Mercer, and your best bet is most likely being eaten alive by big brother Alex..
 * One skit in Tales of Symphonia: Dawn of the New World has Emil acting this way towards Cute Bruiser Presea, much to the consternation of Clingy Jealous Girl Marta.
 * Resident Evil : Leon sure does go to a lot of trouble for Ashley and seems genuinely compassionate towards her, even if it IS part of his job.
 * Oh, he's a very straight example of Big Brother Instinct. Note that Leon is only The Stoic when he's the one in danger, but he'll risk himself without hesitation to protect anyone who needs his help.
 * Chris Redfield is another example. Not only does he go to Antarctica to rescue his sister in Resident Evil: Code Veronica, but in Resident Evil he watches out for the youngest STARS member Rebecca and saves her from a Hunter.
 * Phantom Brave: Ash is very protective of Marona, as she is young girl, hated by pretty much everyone for her ability to summon ghosts.
 * Mega Man: Blues (Proto Man) can be very protective of Rock (Mega Man). He's gone out of his way many times to save his life instead, meaning he keeps an eye on him. Not to mention that he gives a lot of advice to him.
 * Rock himself is the same way. When Wily reprogrammed his brothers, he became Mega Man, took them down, sent them back to the lab to be reprogramed back to normal, and Then defeated Wily with a big loud crunch!
 * And now with Mega Man 10 on it's way, it seems that Mega Man and Proto Man have teamed up to get the vaccine to cure Roll of Roboenza. Whoever created the virus needs to run away now.
 * Final Fantasy Tactics Advance: At least after Marche said he will take care of his brother Doned at the real world.
 * Axel of Kingdom Hearts, towards Roxas, after he started essentially raising the amnesiac Nobody. Sort of a knight templar big brother, given how much of a Poisonous Friend he is. Often misinterpreted as Ho Yay since the whole "raising Roxas" wasn't shown until a sequel released several years after the game where the Big Brother Instinct was initially shown.
 * In the prequel game Birth by Sleep, Terra has this towards Ventus. Threaten a hair on that kid's head and it doesn't matter if you're, he'll still beat you into the ground.
 * Link acts like this towards the children of Ordon and his friend Ilia in The Legend of Zelda Twilight Princess. He does have an actual little sister in The Wind Waker, who causes him to take this trope to the next level.
 * Also in Twilight Princess, he receives the same sort of treatment from Rusl, one of the villagers, who Word of God specifically states considers Link to be his younger brother.
 * Sonic the Hedgehog treats Tails like a little brother. He will also protect him just like a big brother would, as Dr. Robotnik/Eggman learned the hard way in the 8-bit version of Sonic the Hedgehog 2.
 * Sonic sometimes take this role for Cream The Rabbit in several official media's and fanfiction's.
 * Less prominently, Big the Cat of all people seems to act this way to his Team Rose comrades in Sonic Heroes. He is shown comforting and defending Cream on several occasions in the story, Team Chaotix intimidating her marks one of the very few occasions he is genuinely pissed.
 * Infinite Space has Yuri towards his little sister Kira (perhaps a bit too much). There is also Teodoro, who is very protective to his brother, Adolfo.
 * Luke, in the Professor Layton games, has a bit of a big brother complex toward Flora, despite being very obviously younger. It Makes Sense in Context—Luke's known the Professor for a long time and has assisted in a number of investigations, while Flora is a Fish Out of Water in pretty much every situation due to her sheltered background, so both Luke and the Professor are protective of her.
 * Crash Bandicoot for the most part is a mellow Cloudcuckoolander with a pitiful attention span. However he will go through Cortex and every single one of his mooks should they mess with his little sister, Coco. Uka Uka boasting his intention to destroy her once she has outlived her usefulness for his current scheme is about the one point Crash takes the fearsome ancient god mask seriously.
 * Bartz in Final Fantasy V shows this towards Krile, when . He doesn't treat her as weaker or in need of protection, but he does keep an eye on her to make sure she's okay emotionally.
 * Merrill, the ridiculously cute and adorably awkward Blood Magic mage of Dragon Age II seems to have the power to instill this in those around her. Half the party actively looks out for her, especially the amoral pirate captain and the dwarven spymaster, and even Anders starts to look out for her, in his own extremist blood magic-hating way. The only one who truly dislikes her is Fenris, and even then, he tries to get her to change her ways, albeit in the only way he knows how. Even Hawke can easily turn into this if s/he doesn't romance her.
 * Bethany Hawke as well. The first thing Hawke does when they meet Wesley is give the Templar a Death Glare, before he makes clear his intentions. This is the reason her relationship meter is heavily tilted toward "friend." That, and her baaad case of Big Brother Worship (not that the two are unconnected).
 * In Baldur's Gate II, the Player Character gets to be this for Imoen . Granted, you can choose dialogue options that indicate you don't really care, but you still have to rescue her from Spellhold. If you play the game as a good character, though, you are this trope in spades.
 * Corpse Party has Satoshi Mochida, who has this for his younger sister Yuka. Yuuya Kizami, who Yuka meets after she and Satoshi are separated, is also looking for his younger sister.
 * Luigi might have a bit of a "Little Brother Instict" when it comes to Mario. By that, he plowed through a planet-scale army by himself, with his bare hands, and didn't get hit once because Bowser kidnapped Mario.
 * Later, he overcomes his fear of ghosts to save Mario after he got kidnapped by King Boo.
 * Definitely Ezio Auditore da Firenze. In II, the first few missions you get involve helping his infirm little brother Petrucio, and beating the crap out of his sister Claudia's Jerkass boyfriend Ducio. Petrucio's wrongful murder (along with that of his father and older brother) is actually what starts Ezio down the path of the Assassin.
 * For added humor, Ducio turns up years later in Brotherhood, still talking trash about Claudia, and Ezio gets to beat him up again.
 * King from Cave Story has is this towards Toroko. He gets angry when she refuses to give him the key to Arthur's house, but will also fly into rage when she gets kidnapped (and that's without touching red flowers, either).
 * Final Fantasy XIII: Lightning Farron - soldier, all around badass and (most importantly) big sister. Her protective relationship with Hope also serves as the plot device that sets up her defrosting process.
 * Arguably


 * Final Fantasy XIII-2 has a very dark take on this.

Visual Novels
"Ilya: "You said an older brother protects his younger sister, right?... ""
 * In Fate/stay night, Heaven's Feel route, Shirou states that he wants to save Ilya just because "older brother protects his younger sister".


 * In the School Days sequel of sorts Summer Days, Kotonoha's reaction to seeing her younger sister Kokoro  is grabbing a golf club and hitting the culprit upside the head.
 * Yuuya towards Sakuya in Hatoful Boyfriend. Sakuya claims that Yuuya has never once acted like a brother to him, but this couldn't be further from the truth as.
 * Lana Skye from Phoenix Wright: Ace Attorney comes across as an Aloof Big Sister to Ema, but as it turns out, . However,

Web Comics

 * El Goonish Shive: Elliot's Chronic Hero Syndrome appears to have given him a Big Brother Instinct with respect to Ellen despite the fact that his "little sister" is actually his Half Identical Twin / Opposite Gender Clone.
 * Occasionally Elliot has this towards Tedd, like here and here.
 * Ellen has shown she's just as willing to stand up for Elliot when he's threatened/hurt as vice versa. In other life, this is more or less how she befriended Tedd. She got more of this than Elliot with his Chronic Hero Syndrome. She's very uninhibited and shows extreme protectiveness toward everyone close to her.
 * Grace's brothers also have some of this in them, though they don't show it nearly as much as Elliot does towards Ellen. Even though Damien scared them shitless, tried to subvert the orders concerning her as much as he could without being killed.
 * Dominic Deegan tends to act this way toward his cheerful, overly optimistic little brother Gregory. Was kind of justified when the comic started because Gregory was infected with a necromantic taint that was slowly killing him, but it was removed early on and now he's perfectly healthy while Dominic is missing a leg.
 * Arthur from The Adventures of Wiglaf and Mordred has got a bad case of this for his little brother Mordred - so much so it tends to get in the way of his evil villainy. His staff often enjoy pointing out the brother complex he claims doesn't exist.
 * Most of the cast, but particularly Jason, behaves this way toward their younger friend Anna in Something*Positive.
 * Catena: It would be unwise of you to mess with Bear's younger sister Patches.
 * Clark from Gold Coin Comics really shows this side when Tonya, his sister, runs into trouble...
 * Homestuck: Equius is extremely protective of his moirail, Nepeta. In fact, this is the first thing that shows us that maybe he's not that bad a guy.
 * Also, the thought of his twin sister dying is one of the few things that manages to unnerve.
 * In Sakana, it's Taros personal Berserk Button whenever someone threatens or talks bad about his little brother Jiro, and is always there to care for him and cheer him up when he has a problem.
 * Roy in The Order of the Stick develops this for Elan, though it (understandably) takes a while, and he still denies it.
 * Worth noting is that Roy actually did have a little brother, (key word here being did), and Elan has a living twin brother but has been shown explicitly thinking of Roy as his brother instead.
 * And, of course, Roy has a literal little sister, for whom he feels the same protective need (despite crazy morality differences.) Proof? He went to rescue her from villains, knowing fully well that it was a trap all along].
 * In Lackadaisy, Viktor is violently protective of Ivy. To the extent that pretty much every boyfriend she wrangles is pounded to the point of a full body cast. This is particularly noticeable when you contrast it with how he reacts to others, which usually tops off at Vague Irritation at best.
 * Aiden in Winters in Lavelle has this towards his little sister, Kari. It's even been said by Keshii that the main reason why he dislikes Ashton is because he can tell that Ashton has a thing for his sister.
 * Kat in Gunnerkrigg Court once punched a Psychopomp just because these guys made Annie very sad. Later she hates Annie's Disappeared Dad, for the same reason.
 * We're introduced to Elon of Ears for Elves when he's searching for his younger sister Myari after she's run off into the dangerous forest. He gives her a severe talking-to, but has her best interests at heart.
 * Layla in Eerie Cuties mostly considers Nina embarrassing. But also... "YOU. MADE. MY. LITTLE. SISTER. CRY!!!"

Web Original

 * Broken Saints: Heartwarming Orphan Shandala, the heroine, is looked after by her adopted parents' son as if she were his own flesh and blood.
 * Dimension Heroes: Rob displays this trope towards his fellow Dimensional Guardians, reasoning that as leader, he's responsible for their safety.
 * Decembersville: Nutty Jimmy is like this to his sister, Sarah. As illustrated here.
 * Rob Walker will be the first to admit anything that didn't work out in a Critic-episode, but if you go too far and insult Doug instead, he will make you sorry.

Western Animation
"Candace-2: I'll do anything to protect the ones I love."
 * Mako from The Legend of Korra spent his childhood watching over his brother Bolin. And he still totally is in his adulthood.
 * Bolin himself counts, too. When Korra receives gifts from Tarrlok in front of him, Bolin offers to "have a word with the guy," as he thinks she's being harassed by a Stalker with a Crush.
 * The X-Men character Wolverine often acts as a mentor to one of the younger heroines on the team: Kitty Pryde (comics), Jubilee (comics/animated series), or Rogue (film/second animated series).
 * Danny Phantom: Danny does this with his Opposite Gender Clone. Interestingly, he develops this instinct even with his older sister, becoming overprotective when she's in trouble or in the rare moments when she does something irrational.
 * The Simpsons: Bart Simpson usually couldn't give a damn what happens to Lisa on a mundane basis, and the two have an intense sibling rivalry, but his instinct does kick in every time something serious happens.
 * Loopy's older brother Larry on KaBlam!'s "Life with Loopy" shorts is like that towards her.
 * Avatar: The Last Airbender: Sokka and Katara switch off in who's taking care of who when it comes to the group.
 * Perry the platypus from Phineas and Ferb seems to be like this to the title characters, judging by how much more viciously he attacks his nemesis Doofenshmirtz when his current scheme would put Phineas and Ferb into danger. Possibly to Candace as well, but it's hard to tell.
 * In the movie Phineas and Ferb The Movie: Across the 2nd Dimension, Candace-2 from the alternate dimension is fiercely protective of her brothers Phineas and Ferb.

"Tigger: Only the best...for my bestest little brother..."
 * In Ed, Edd 'n' Eddy, Ed is this to Sarah.
 * Sarah herself is this to Jimmy, she maybe is a Spoiled Brat but this is arguably one of her redeeming qualities.
 * Skipper and Kowalski of The Penguins of Madagascar display this toward Private occasionally, covering his eyes or ears to protect him from "inappropriate" content.
 * Ben 10: Alien Force and Ben 10: Ultimate Alien: Despite their differences Kevin acts this way towards Ben.
 * Franklin: Turtle, without a doubt, seen in the third season in "Big Brother Franklin" when Franklin took to looking after a little kid named Squirrel. He also became a "best friend big brother" to Bear's little sister, Beatrice. Eventually, Paulette Bourgeois finally made him a big brother for real in the book "Franklin's Baby Sister" and the film Franklin and the Green Knight soon followed.
 * Wild Kratts has the Kratt Brothers, who both play it straight and invert it. Most obvious in episode 20 when, even though Martin's been turned into a tree, he's still worried for little bro Chris and how his current small size makes him a target for many, many predators.
 * In Generator Rex, Rex's older brother Cesar instantly goes into protective mode after their reunion and tries to 'rescue' Rex, even though Rex isn't in any danger. He later knocks out a bunch of Providence agents and jumps down from a ship to help Rex fight an Evo.
 * Winnie the Pooh isn't particularly smart to say the least, though he will constantly aid and comfort Piglet as much as his hapless self allows. Similarly Tigger is something of a Keet, though cares a lot about Roo. With a fair helping of Big Brother Worship in there from the latter, both even refer to each other as brothers. Both of these are seen in the original novels, though it is the Disney incarnations where this trope is most evident.
 * Winnie the Pooh isn't particularly smart to say the least, though he will constantly aid and comfort Piglet as much as his hapless self allows. Similarly Tigger is something of a Keet, though cares a lot about Roo. With a fair helping of Big Brother Worship in there from the latter, both even refer to each other as brothers. Both of these are seen in the original novels, though it is the Disney incarnations where this trope is most evident.


 * Kenny McCormick from South Park cares a great deal about his younger sister, Karen. So much so that  Awww.
 * Alternatively and less immediate, Kyle and Ike's relationship has varied throughout the course of the show; originally, Ike was more of an Annoying Younger Sibling who idolized Kyle, following him to school and copying his mannerisms, while Kyle held a more superficial malice towards his brother (when he learned Ike was adopted, he completely shunned him for a while). Nowadays, Kyle goes to great lengths to keep his little brother safe, from stopping him from running off to Somalia, to dragging his friends to Canada on Christmas Eve to get Ike back from his biological parents. Ike has now become one of Kyle's greatest drives (seconded only to Kyle's antagonism towards Cartman.)
 * In the 2011 ThunderCats, Tygra often struggles with his deep resentment of his younger brother Lion-O, but when Lion-O is protecting some stockaded prisoners from an Angry Mob and has challenged them to Go Through Me, Tygra immediately comes to his aid informing the crowd "You better be sure you want to do this because I've got his back."
 * Star Wars: The Clone Wars: Obi-Wan to Anakin, who in turn is to Ahsoka.
 * Codename: Kids Next Door:
 * Cree was this towards Abby (Numbuh Five) before she turned evil and they became enemies. At least one episode suggests Cree wants to reconcile, but only if Abby is the one willing to change sides.
 * Played straight with Numbah Four towards his baby brother Joey, although "Operation: D.O.D.G.E.B.A.L.L." shows that Joey isn't exactly a slouch.

Real Life

 * Bobby Kennedy had a raging overprotective little brother instinct towards his big brother. Apparently, his fury could scare the shit out of anybody if they tangled with John. Especially if it was LBJ (Lyndon B. Johnson).
 * LBJ was no slouch either. He was a master at cajoling Congress into doing whatever he wanted because, damn it, he was LBJ. The fact that Bobby could match him and actually make him back down is pretty amazing.
 * James McNeil, age 17 saw his autistic ten-year-old brother climbing to the top of an 120-foot electrical tower. Though fearful of heights he climbed after him and held him in place until a rescue crew arrived. The story is described in the November 1997 Reader's Digest.
 * In 2009, nine-year-old Malik Medford rescued his brothers from a car thief.
 * Another inversion, an eight-year-old boy was killed after wounding a burglar who was attempting to rape his older sister.
 * A real-life inversion: in 2002 Christopher Vince, aged 12, died after pushing his 16-year-old brother Ben out of the way of a falling branch.
 * In a real-life example of big sister instinct a nine-year-old girl risked her life to push her five-year-old sister out of the way of an oncoming truck.
 * This eleven-year-old, who protected his younger sister from a carjacker.
 * Members of a fraternity are supposed to develop this, as the house is set up for a big brother to look after a little brother (pledge).
 * A twelve-year-old Florida boy saved his four siblings from a fire.