Big Little Brother

When someone mentions his or her “little brother”, you usually expect a smaller, weaker individual, most likely a child or teenager. The big little brother is the polar opposite of this. It’s someone who may be the youngest member of his family, but just so happens to be stronger, taller and overall more physically impressive than his older siblings. The revelation of this usually comes as a surprise to both the audience and the characters in a story. This trope is usually used for comical effect.

Anime & Manga

 * Fullmetal Alchemist
 * Alphonse Elric is the little brother of Edward Elric, but because his body has turned into a suit of armour he is much taller and stronger than his older brother.
 * While he is her younger brother, Major Alex Armstrong is still a good head taller than General Olivier. Of course, that doesn't make her any less intimidating.
 * The Toguro brothers in Yu Yu Hakusho. Elder Toguro was a short, lanky, immortal trickster. Younger Toguro was a Blood Knight who lived for fighting and, as such, has honed his already tall and muscular figure to buff up when using his full strength. He was also the stronger of the two by a wide margin.
 * In Axis Powers Hetalia, England comes back from a long absence, and is disturbed to find his adopted younger brother America has suddenly grown taller than him. China's (presumably adopted) younger brother, South Korea, is a head taller than him, though it's never mentioned. Prussia's younger brother Germany is taller than him too, though this is also not mentioned.
 * Same goes to Russia, who is more than One Head Taller than his beloved older sister Ukraine. Also not quite alluded to.
 * Shingo Tsukino in Sailor Moon isn't taller than his sister Usagi but he is smarter, stronger, and often regarded as more mature than her. Then in the second season he starts catching up to her in the height department, and by the fourth season the kid's almost taller than she is.
 * Although not taller then him, the younger Kongo twin in Eyeshield 21 beats his older twin in absolutely everything, needless to say the elder brother has a bit of an inferiority complex as a result.
 * Yukio is this to Rin in Blue Exorcist. Ironically, because Yukio was weak as a fetus, all of Satan's demonic powers went to Rin.
 * Elfman to Mirajane (but not Lisanna, who is actually the youngest sibling) in Fairy Tail.
 * Mitsukuni Haninozuka from Ouran High School Host Club is much shorter than his younger brother Yasuchika.
 * Boa Sandersonia and Boa Marigold from One Piece are both taller than their eldest sister, Boa Hancock. And this is considering that Hancock herself is already more than 6 feet tall.
 * Also, who even as a baby was much bigger than her brothers.
 * Michio Kawata from Slam Dunk is way taller than his older brother Masashi. Also Sibling Yin-Yang: Michio is a Gentle Giant while Masashi is Hot-Blooded.
 * Exaggerated in Recorder and Randsell: Atsushi Miyagawa is a fifth grader who looks 17. On top of this, his older sister is in high school and looks his age.
 * Yuki Aiba of Infinite Ryvius. Even though his older brother Kouji is the protagonist of the series, Yuki is a bona-fide Ace, while Kouji barely squeaks into Dogged Nice Guy territory. Yuki is taller, stronger, bolder, is better looking, is better a fighter, a better pilot, a better tactician, and has a more active love life than his older brother. Kouji's only saving graces are that he's more responsible and better organized than Yuki.

Comics -- Books

 * The Belgium comic strip Suske en Wiske uses this trope in at least two albums. In de malle mergpijp, Jerom is forced to fight a giant grotkastaar (an ape-like inhabitant of Jerome’s prehistoric homeworld) who is the “little brother” of a much smaller and less impressive grotkastaar. In the album de glanzende gletsjer, Lambik finds himself in a world inhabited by cave men, who force him to fight against the little brother of their chief; a tall and muscular cave man.
 * The French comic Asterix uses this trope in the album Asterix at the Olympic Games. During the games we see a big, muscular man fighting in the arena while his older brother encourages him from the sideline. When Vitalstatistix asks him if everyone in his family is this strong, he mentions he has an even younger brother who is even stronger than both of them..
 * From Lucky Luke, Averell Dalton in the youngest and the tallest of the Dalton brothers. He's also implied to be the strongest in their first appearance, but it isn't mentionned after that.
 * Colossus from the X-Men was the youngest of the "All-New, All-Different" team, being 17 or 18 when recruited, but he was also the Big Guy and towered over the others in his metal form.

Films -- Animation

 * The Land Before Time: Spike is the adopted little brother of Ducky, but is much bigger than her because he is a stegosaurus and she is a saurolophus.

Films -- Live-Action

 * Four Brothers: The youngest of the four Mercer brothers, Jack, is by far the tallest of the lot. They are all adopted, after all.
 * Invoked verbatim in Flight of the Navigator, where thanks to time travel, the main character's "little brother" has aged past him.

Literature

 * In World Without End, Ralph is this to Merthin.
 * Jack Reacher is the younger brother, but he is the better fighter and physically bigger than his brother.
 * The Dresden Files: Six-and-a-half-feet-tall Harry Dresden is also more powerful than his six foot nothing older brother, though Thomas is physically stronger.
 * Played with (for laughs) with the Gruffs. The Gruffs (as in, Billy Goat) are the Summer Queen's troubleshooters (trouble? they'll shoot it), and each one is progressively larger than the one before, just like in the fairy tale. After having fought off one marginally smaller than a school bus and having been warned that its big brother was on the way, Harry begins to be seriously worried. When Harry realizes that last one has him cornered, he starts making his peace. On the way in, the Eldest Gruff casually destroys a Denarian (a Fallen Angel in a mortal host) with love and happiness.
 * Harry Potter and The Order of The Phoenix: We get to meet Hagrid's little brother, Grawp. Grawp, being a full giant instead of just a half giant, is 16 feet tall (which makes him small, by giant standards).

Live-Action TV

 * In The Super Sentai series Battle Fever J, many of the Egos Monsters from episode 5 onward have "little brother" giant robot doubles.
 * Kaizoku Sentai Gokaiger has Younger Brother be an average-sized Monster of the Week. Elder Brother is the size (and shape) of a baseball.
 * Everybody Hates Chris has Chris's younger brother, Drew, being both taller and much cooler. Chris is quite aware of it.
 * Inverted on The Suite Life of Zack and Cody: Moseby's older brother Spencer is a little person. Spencer is also stronger, more wealthy and a grade-A Jerkass.
 * Sam Winchester from Supernatural, on account of Jared Padalecki being about 6'4 and Jensen Ackles being about 6'1.
 * Alcide Herveaux from True Blood is a walking mountain of muscle, but his older sister Janice still refers to him as her "baby" brother.
 * On Hercules: The Legendary Journeys, Aphrodite often refers to Herc as her "big brother," even though she's older than him by centuries.
 * One episode of The Beverly Hillbillies had Mr. Drysdale be informed that the little brother of one of his secrataries wanted to have a talk with him. His reaction was "Send the little fellow in! I'll give him a piggy bank!" The "little fellow" was built like a linebacker.
 * Rodney to Del in Only Fools and Horses.

Video Games

 * Light example with Crash Bandicoot. Coco is often slightly taller and significantly more intelligent and sane than her "big brother" Crash (granted this depends on the creative team, in Mind Over Mutant for example she is shorter than Crash and almost as demented and childish as he is).
 * Played with in the Super Mario series. Luigi is taller than Mario and has his own moments of impressive heroism, however he is also rather cowardly and frequently lives in his big brother's shadow.
 * Final Fantasy VIII has a Summon of two Minotaur brothers which make use of this trope. Of course after you fight the first one and he goes to get his Big Brother, it's alluded to that his Big Brother is literally bigger than he.

Web Animation

 * Strong Sad from Homestar Runner is not only a lot taller than Strong Bad, he's also wider. Besides this, he's also shown to be almost always smarter. He probably only lets Strong Bad pick on him because their elder brother Strong Mad is Strong Bad's ally and is even bigger than Strong Sad himself.

Web Comics

 * Prince Ossomer of Erfworld is the youngest, tallest and most muscular of the three Jetstone Princes. Inverted by Prince Tramennis, the eldest and smallest.
 * Order of the Stick has a variant in Start of Darkness prequel book -- Redcloak is immortal, so by the end of the story his younger brother appears decades older than him.

Web Original
"Dana: Everyone has an older brother that overshadows-- Tom: I... I didn't say he was older. Zack: Tom's a loser!"
 * Tom in Echo Chamber was overshadowed by his little brother, which serves as his Freudian Excuse for being a Jerkass to Zack.

Western Animation

 * Exaggerated in The Proud Family with the Gross sisters. The youngest sister in the trio towers over everyone, while the oldest is a half-pint.
 * Don from Regular Show, a fancy accountant who is tall, muscular, and popular. He is also Rigby's little brother. Made extremely jarring by the fact that, out of the cast of mostly-Funny Animals, Don is the most human-looking character -- more so than the human characters themselves -- and he's stark naked. And constantly wants some sugar from his big brother.
 * In Family Guy, Chris is the biggest Griffin child, but Meg is the oldest. The actual height difference is relatively minor, though he's also quite a bit heftier.
 * Stewie Griffin: The Untold Story shows that the older siblings remain roughly the same height into adulthood, while Stewie grows up to be quite tall and lean.
 * Sherman Cortez in Hot Wheels Battle Force 5.
 * In The Simpsons, Todd Flanders is taller than his older brother Rod.

Real Life

 * Often Truth in Television, especially for a lot of guys with older sisters. If genetics are kind to you there eventually comes a wonderful day where you find yourself looking down to see your big sister.
 * The younger siblings often tend to be taller than their older siblings, even with girls. It's not that uncommon for an older brother to have a sister who's the same height as or taller than them.
 * This can also be disconcerting for the older brothers of tall guys...although sometimes, the shorter brother makes up for it by being substantially stockier.
 * Of course, if the younger brother is muscular in addition to tall, you're just screwed.