Intergenerational Friendship



Two people are good friends. Only, one is about twice, or even three times the other person's age! Considering their differences in life experiences and worldviews, how do they relate? What could they possibly have in common? Assuming this is actually a platonic friendship and not something far more sinister, or for that matter an overtly stated mentoring situation, intergenerational friendships can be pretty weird. As the Real Life section indicates, while not everyone finds older or younger people completely unapproachable, there's still frequently a gap there.

This can take the form of a young adult from one generation befriending someone old enough to be their parent or even grandparent, such as in the comedy Finding Forrester. It can take the form of an adult befriending a misguided or vulnerable youth, as in the French film Leon. Sometimes, the two happen to have more in common than they think, such as having surprisingly similar life experiences.

As for how they become friends, it could well be contrived circumstances that bring them together, or a shared life experience. Sometimes it's a teacher trying to help a troubled teen, leading to them becoming close friends. Either way, the situation that leads to their friendship would often be something out of the ordinary, since in real life, people of two widely different age groups generally do not reach out to each other.

If it's an adult and a child who are friends, in modern stories, expect someone to misinterpret it as being sexual, and violence to possibly result. Sometimes the younger one will have an innocent Precocious Crush on the older one.

This trope does generally not apply if it's a parent-child relation between the two.

A subtrope of Odd Friendship. Contrast May-December Romance, in which there is a generation gap between romantic partners.

Anime and Manga

 * In the anime version of Sailor Moon, the no-more-than-eight Chibi-Usa is good friends with Setsuna, who is at least in her late teens, but more likely early-to-mid twenties. Then throw in the fact that the Setsuna Chibi-Usa is friends with originally is the thousand-year-old (AND reincarnated) Sailor Pluto, and the gap is a bit bigger. In the manga, on the other hand, Chibi-Usa herself is over nine hundred but looks like a child, and even then Setsuna is significantly older than her.
 * Rei Hino (14) and Kaidou-san (early/mid 20's) in the manga.
 * Many relationships in Tower of God, due to the different life spans of the races and the life-prolonging characteristics of Shinsoo.
 * Kids like Koon and Hatsu are in their late teens while their good friend Ship Leesoo is in his 30s, whereas Baam is probably several hundred years old.
 * Anak has an Odd Friendship going on with her aunt Androssi, who is actually much younger than her.
 * From Bleach, Kenpachi Zaraki met his lieutenant when he was at least a 20-something-year-old (apparently) killer and she was a little baby. She's still very young relative to him, and almost totally opposite. And she likes him. Go figure.
 * Mind you, she's basically his adoptive daughter and their relationship reflects that.
 * We also have an interesting case with Nel, who is a child, and Ichigo, a teenager. Then, we find out that
 * Gene Starwind (aged about 20) and Jim Hawking (aged 11) in Outlaw Star.
 * Bear (middle-aged writer) and Mimiru (high school student) in .hack//SIGN. Gamers from different generations playing a virtual reality MMORPG. "You know, when I was your age, we actually had to use graph paper to map out the mazes in games." "You are old."
 * Watanuki (about 16) and Kohane (about 10) in xxxHolic
 * Watanuki and Yuko (in her late 20's ), and Watanuki and Haruka).
 * Negi (10) and Takahata (mid 30's) in Mahou Sensei Negima. Kind of makes sense as Takahata was a friend of Negi's father Nagi.
 * Within the Ala Rubra, Eishun is at least 10 years older than Nagi, and Albireo is implied to be even older than that. Jack Rakan is also probably at least a decade older than Nagi. And Takahata was about Negi's age back then. The only one within his same age range was, who was no older than 14.
 * Chisame (14 as much) and Jack Rakan also seem to have a bit of an Odd Friendship going, as well, especially judging by
 * Not to mention Chisame's seeming addiction to age-changing pills to make her a loli further emphasizes this..
 * Simoun gives us the deep and mutual bond between sixteen-year-old Yun and Time Abyss Onashia, possibly the ultimate example in terms of actual age difference.
 * Fate and Signum of Magical Girl Lyrical Nanoha, who first became friends back when Fate was just 9 while Signum... looked and acted to be around 19 but is actually a few hundred years old.
 * Sousuke (16) and Kalinin (40-50+ ?) from Full Metal Panic!. Kalinin doesn't quite make it as Sousuke's father figure (Majid took that role), and is more of a intergenerational Heterosexual Life Partner (though this is most notably during their backstory where they spent more time together - Kalinin shows up a lot less in the present time of the series).
 * But note that Kalinin is Sousuke's legal adopted father, and he cared for the kid ever since Afghanistan.
 * Professor Oak (about 50) and Ash (10 for the past ten years or so) in Pokémon are fairly close even though the former taught Ash's mother in school. Possibly averted in that, at least on Oak's end, he first met Ash when he was the same age due to some accidental Time Travel.
 * Kurogane (mid-twenties), Syaoran, Sakura (teenagers), and Fai (at least 50) from Tsubasa Reservoir Chronicle might count as this.
 * Himura Kenshin and Sagara Sanosuke in Rurouni Kenshin are 28 and 19 respectively, yet they gamble, drink, and occasionally swap war stories (from the same war, no less). Sano tends to act more grown up most of the time (outside of combat situations).
 * People tend to mature quickly in the war. Kenshin was Sano's current age during the late part of it, and Sano himself was a Child Soldier.
 * More vitriolic, but also quite loyal: Sanosuke and 10 year old Yahiko Myoujin.
 * Shirou and Ilya in Fate/stay night.
 * Yuzuriha (14) and Kusanagi (about 40) in X 1999. The girl is in love with the man, but it's implied that he cannot be anything more than friends with her due to their age difference and squick factor.
 * An example from the same series is Subaru and Seishirou. It's not as obvious in X 1999 where both are clearly adults, but in the semi-prequel Tokyo Babylon the age gap is much more visible, Seishirou being 25 while Subaru is only 16.
 * Heero Yuy (14-15) and in Gundam Wing.
 * Eclaire Tonerre (16-17) and 's mother (most likely in her fourties) in Ouran.
 * Mamoru Amani (9) and Gai Shishioh (20) in GaoGaiGar.
 * Neon Genesis Evangelion has Misato (29) and Shinji (14).
 * Several of Luffy's True Companions in One Piece. Up to the Grand Line, all of the crew were in their late teens. Then came Chopper (15), Nico Robin (28), Franky (34), and Brook (88; about 38 alive and spent around 50 years as a skeleton).
 * Also Luffy's friendship with Shanks.
 * Let's not forget Mr. 2, who is very keen on making speeches about his friendship with the Straw Hat Pirates. His age hasn't been revealed - actually he's a bit of a Vague Age case - but it can probably be assumed that he is about twice as old as Luffy and the other five youngest Straw Hat Pirates.
 * Gohan and Krillin in Dragon Ball Z, particularly in the Namek saga, where they spend a lot of time working together trying to think their way around the much more powerful villains. The weird thing is that Krillin isn't much taller than the four-year-old Gohan. Piccolo and Gohan could also count, though it's more master/student than friend.
 * Well, Gohan and Piccolo doesn't really count, since Piccolo's only four years older than Gohan.
 * Fullmetal Alchemist has cute, Plucky Girl Xingese princess Mei become good friends with the Hero-Killer, Ishvalan ex-priest Scar, who is on a Roaring Rampage of Revenge. It helps that Mei is a Horrible Judge of Character.
 * The manga also has Roy Mustang, age 29, mentored by and (at least to appearances) pretty good friends with General Grumman, who is old enough to be his grandfather.
 * and Jajuka (age unknown, but presumably in his twenties) in Vision of Escaflowne.
 * Kiki from Kiki's Delivery Service, who befriends three women, all of different ages. There was the pregnant baker lady, the teenaged artist and an elderly woman.
 * The Yorozuya trio in Gintama. There's Kagura (14), Shinpachi (16) and their boss/comrade/friend/sorta-like-big brother Gintoki, whose age has been stated to be around 20s. Kagura even sleeps in Gintoki's closet. It's her room.
 * From Hikaru no Go: Hikaru Shindou who is around 12 years old at the beginning of the story, and Fujiwara Sai, who is a couple hundreds years old ghost.
 * Suzu (12) and Akira (somewhere in her 20s) in Rakugo Tennyo Oyui. Suzu spends the great majority of the series hanging around high school students and old famous people from Japanese history. If it weren't for the tanuki, Ponta, she'd be the only person of her age around.
 * In Durarara, Shizuo Heiwajima (24) tends to develop friendships with people that are out of his age range, such as Simon (late 40s to mid 50s), Akane (10), the twins Mairu and Kururi (15 as much), and Celty (200+).
 * Cardcaptor Sakura has Sakura (10) and Kaho Mizuki (20s). All of friendships might count as well, taking Really Seven Hundred Years Old into account.
 * Iceland (ageless nation, but with the looks of a 17-year-old) and Turkey (also ageless nation, looks like in his mid-to-late 30's) in Axis Powers Hetalia. More exactly, the Hetalia Bloodbath 2010.
 * Also France (ageless nation who looks like in his late 20's) and
 * Any of Break's friendships in Pandora Hearts count as this as although he doesn't look it he's nearly forty. His closest Friends are Reim (26) and Sharon (23, although she looks 13) they've been friends since he was 24.
 * In Wandering Son, Shuichi and Yoshino both make friends with two adults in their twenties or thirties when they're around nine years old.
 * Yugi and his friends in Yu-Gi-Oh (all around 16) with Pharaoh Yami (over 3,000).
 * Persona 4: Nanako Doujima (6) and all of her cousin Yuu's friends (around 15-16), but specially 15-year-old Naoto.
 * Eyeshield 21 has Sakuraba (a high school student) and Torakichi (a grade schooler) who is Sakuraba's biggest fan and one of Sakuraba's main motivators for improving himself.
 * In the prequel Saiyuki Ibun, it is played with Toudai (who will be known as the Goudai Sanzo) and the youkai Tenkai who would inherit the Maten Sutra before Koumyou Sanzo. Physically, Toudai appears much older than Tenkai who looks like a young child. But as a youkai, Tenkai could be easily be years older than Toudai while retaining his youthful appearance.
 * Aoki-sensei (22) and the three girls (10 each) from Kodomo no Jikan act like this from time to time. Kuro (10) and Shiro Ch... I mean Shirai-sensei are an even better example.
 * Aoki-sensei (22) and the three girls (10 each) from Kodomo no Jikan act like this from time to time. Kuro (10) and Shiro Ch... I mean Shirai-sensei are an even better example.

Comic Books

 * The relationship between Johnny and Squee in Johnny the Homicidal Maniac is something like this, with Johnny regarding Squee as a friend/little brother figure. It's entirely one-sided however, as Squee doesn't feel anything other than sheer terror towards him, and with VERY good reason.
 * Lenore and Ragamuffin from Lenore the Cute Little Dead Girl is one of the most extreme cases. Biologically, Lenore is 10 years old and Ragamuffin is between 20 and 30 years old. The thing is that Lenore has been 10 for 100 years and Ragamuffin has been 20-30 for 400 years. So they are like 4 generations apart and Lenore is still the one who manipulates him like he is her toy... which he is, practically, since he is trapped in a small cotton doll.
 * And even when he transforms into his old vampire self, he still follows her like a devoted servant friend.
 * Dennis the Menace US, when Mr. Wilson is friendly.
 * Wolverine and every teenage girl to join the X-Men. In particular Jubilee in the 80s-90s, Kitty Pryde, and Armour more recently. In fact he appears to get along with teenage girls better than any other type of person.
 * Lampshaded in an old Wolverine issues, "do you wonder, why this need for adolescent girls?" - to which Jubilee replies "coz we don't screw his heart and backstab him after like you [adult] cows always do".
 * In the excellent but very grim Dark Horse Comics series Kings In Disguise, involving hoboes in the Great Depression, the main character is a young boy who ends up teaming up with a much older man while searching for his father. There's nothing sinister at all about their friendship, but many other hoboes traveling with young boys are in exactly that sort of relationship, and they assume that these two are as well. That's not even mentioning the incredibly creepy old guy who tries to assault the protagonist at one point.
 * Oliver Queen has this relationship with the current Speedy, Mia Dearden. She had a small crush on the Emerald Archer in her early days as his sidekick, but then along came G.A.'s son, Connor Hawke...
 * Asterix's closest friend besides Obelix is the druid Getafix, who had his long white beard when all the rest of the cast (save Geriatrix) were children.
 * All of Tintin's friends are either much older (Captain Haddock, Cuthbert Calculus) or much younger (Chang) than he is.

Fan Fiction

 * The Second Try has one develop between and 14 year old Rei. This is especially interesting because . And because
 * A Cup of Kindness has another example.
 * Getting Back on Your Hooves has Trixie form one with the Cutie Mark Crusaders after she saves them from a Ropen in the Everfree Forest (though Sweetie Belle already liked her before then).

Film

 * Will, the isolated, delinquent, genius teenager from the slums of Boston, and Sean, the middle-aged, dissatisfied and lonely community college psychology professor form a relationship that makes up most of the plot of Good Will Hunting.
 * Finding Forrester is about a high school student, Jamal, who meets reclusive author Forrester, and the two become friends. This leads to funny moments such as when Forrester tries to act "hip" by speaking slang, leading to the infamous "You're the man now, dog!" phrase.
 * Lawn Dogs is about two disaffected outsiders, a 10-year-old girl and a 21-year-old lower-class man, who become unlikely friends after a chance encounter. As mentioned above, it does indeed lead to violence when people begin to suspect the worst. Some viewers believe that Devon has a Precocious Crush on Trent, which could complicate the situation.
 * Leon (aka The Professional) involves an assassin who befriends a 12-year-old girl.
 * Taxi Driver is about a man who befriends a 12-year-old girl as well.
 * The City of Lost Children has a 9-year-old girl who befriends an intellectually disabled man whose younger brother was kidnapped.
 * Beautiful Girls has a very young girl (played by Natalie Portman from The Professional) and an older man.
 * In Back to The Future, high school senior Marty McFly is probably elderly scientist Dr. Emmett Brown's only friend in town. At least in the movies, how they met and became friends is not explained. That relationship simply exists before the first movie begins.
 * An early shooting script for the film says that in 1983, Doc came by the McFly place and offered Marty $50 a week plus free beer and use of his record collection to clean up his garage; this explanation is typically discredited by fans because it clashes with the characters as seen in the movie. In the end, the film's creators decided not to bother expanding on the history.
 * Word of God later explained that the friendship started when Marty was around 13-14 years old. After being told for years that Doc Brown was a dangerous, crackpot, lunatic, he snuck into Doc's lab to see for himself and instead was fascinated by what he saw in there and thought Doc's inventions were cool. Doc found him and was happy Marty thought he was "cool and accepted him for what he was". Doc then gave Marty a part-time job helping out with experiments, helping in the lab, and feeding Einstein. Read for yourself here.
 * I kinda felt it was obvious. Doc needs somebody to film his experiments, and Marty needs a kickbutt amplifier that goes Up to Eleven. Symbiosis works, folks.
 * It probably didn't hurt that Doc knows that he has to be friends with Marty if he wants to avoid a time paradox.
 * Later it was established that Doc actually sought Marty out when the timing was right due to his knowledge of their future friendship.
 * Middle-aged accountant Henry "Mutant" Weston and nine-year-old Eric from Mr. Magorium's Wonder Emporium.
 * Plus, Mahony and Mr. Magorium himself. Sure, she might be about 20-30, but he claims to be 243 years old.
 * The Fall centers upon the relationship between Alexandria (5), a young immigrant with a broken arm, and her reluctant father-figure Roy Walker (unknown -- based on the actor's age, mid-20s), a paralyzed stuntman. Surprisingly, no one ever suspects anything "funny" between them; the fact that he's a paraplegic may be a factor, but even after hospital officials find out that Roy conned Alexandria into stealing him morphine, he's still allowed to see her.
 * The film Scent of a Woman is about a poor prep school student slowly developing one of these with a blind, medically retired ex Lieutenant Colonel who has hired him as aide.
 * Lost in Translation is about Bill Murray's character and Scarlett Johannson's character striking up a friendship in Japan, in part because they are both in unsatisfying relationships with their spouses. The ending is ambiguous over whether it is a romantic relationship, but it does not have to be.
 * The Man without a Face features a disfigured recluse (played by Mel Gibson) who agrees to tutor a troubled young boy over the summer. Their friendship sparks suspicion amongst the town residents. (Of course, in the book... )
 * About a Boy. Will Freeman, a 36-year-old bachelor, and Marcus, an eccentric, introverted, bullied 12-year-old with a suicidal mother end up close, and Marcus benefits and gradually becomes more confident and "normal" as a result of Will's guidance.
 * In keeping with modern concern about such relationships, Marcus's mother initially thinks Will must be a paedophile and has a go at him in public.
 * I thought Will was 38?
 * Walt and Tao in Gran Torino.
 * Indiana Jones and Short Round in Temple of Doom.
 * The Ultimate Gift has the rich twenty-something guy befriend the Littlest Cancer Patient.
 * Rigoletto, a man who's at least in his forties and probably older, is reluctently befriended by a young girl to whom he ends up giving music lessons. The other kids from her town end up befriending him as well, with some pushing from the young girl. The adults are pretty wary, due in large part because the man is pretty badly disfigured. It all blows up when it appears that Rigoletto attacked a child.
 * It's worth noting that Rigoletto
 * Uptown Girls included one of these.
 * Daniel LaRusso and Mr. Kesuke Miyagi in the The Karate Kid movies. Also Miyagi and Julie in The Next Karate Kid.
 * It continues in the 2010 remake, with Dre and Mr Han. And it also achieves a Crowning Moment of Heartwarming when Dre calls Mr Han his best friend.
 * Hogarth and Dean in The Iron Giant.
 * Carl and Russell in Up.
 * Buster with Elwood and Mack (and later, Cab), in Blues Brothers 2000.
 * The beautiful film Yaaba is about two African children befriending a very old woman, an outcast who is accused of being a witch.
 * Max Fischer and Herman Blume in Rushmore.
 * In Finding Neverland, James Barrie strikes up a friendship with the Llewelyn-Davies boys despite being old enough to be their father. It helps that James is very much in touch with his inner child and that two of the boys (Peter and George) often act mature beyond their years.
 * And since the movie is loosely based off of the real life friendship between James and the Llewelyn-Davies family, this would be Truth in Television.
 * Rebellious Princess Jen from Crouching Tiger, Hidden Dragon strikes up a sisterly friendship with Lady of War Shu Lien, who is at least twice her age.
 * Mary and Max is a film about the friendship between an 8 year old girl and a 44 year old man.
 * Prominent in the Terminator franchise. In Judgement Day, John Connor (10, or possibly 13) and T-800 (ageless, being a robot, but looking like a man in his 40's) develop this kind of dynamic. In ''Terminator: Salvation", Kyle Reese (ca. 16) and Marcus (ca. 35) become not only friends, but real battle brothers.
 * In Push, the 13-year-old Cassie and Nick, who is in his mid-20s, are reluctant partners when they are chased by the Division and the Triads. By the end, though, they develop a friendship.
 * The Fellowship in Lord of the Rings, all with varying ages. Gandalf and Legolas were definitely the oldest of the group, with Pippin being the youngest and Aragorn's age is stated to be 87.
 * In Montreal Main, a photographer in his late 20s becomes best buds with a 12-year-old boy. Whether or not there's some attraction there is ambiguous; Word of God states that the man "doesn't know what he wants".
 * Allan Quatermain and Tom Sawyer develop one of these in the film version of The League of Extraordinary Gentlemen.
 * Henry Travers who plays the heroine's father in Shadow of a Doubt was about seventy at the time of filming. Hume Cronym, who played his best friend, Herbie, was about thirty. Originally Herbie was supposed to be played by a must older actor but they liked Cronym so much they they cast him. What results is a charming Intergenerational Friendship.

Literature
""I can assure you," he said with a slight smile, "Zachariah can be a fine friend." "And I can assure you," I returned, "that the captain will have made arrangements for my social needs." "Ah, but you and I have so much in common." "I don't think so." "But we do! Miss Doyle is so young! I am so old! Surely there is something similar in that.""
 * In The Bartimaeus Trilogy, Bartimaeus is a demon, thousands of years old and was pretty close friends with Ptolemy and, in the end, is pretty close friends with Kitty and especially Nathanael; all three of them are/were in their teens at that time.
 * In The True Confessions of Charlotte Doyle, Charlotte is 13, while Zachariah is in at least his 60s. It makes sense to Zachariah, though:


 * David and Jonathan in The Bible.
 * Jim and Huck in The Adventures of Huckleberry Finn
 * Low Men in Yellow Coats, the first story in Stephen King's book Hearts in Atlantis (later made into a Film of the Book) is about a young boy who develops a friendship with the much-older psychic Ted Brautigan. The boy's rather self-centered mother harbors strong suspicions about Brautigan's intentions for her son, which figures heavily into his eventual capture by the inhuman creatures hunting for him at the end of the story.
 * Another King example is Jake and Roland in The Dark Tower series. Jake is not quite a teen when they first meet, and Roland is well over fifty.
 * King again, in Pet Sematary, with the Crandalls (both eighty-something) and the Creeds (in their 30s, with two young children who also bond with their elderly neighbors). When they first meet, the narration describes Louis Creed's relationship to Jud Crandall by saying "he called this man a friend, as a grown man must do when he finds the man who should have been his father relatively late in life".
 * Sandor Clegane and Sansa Stark in A Song of Ice and Fire. Not quite a friendship, but certainly a case of Strange Bedfellows.
 * Many books by Russian author Vladislav Krapivin feature this trope, with friendships between a child and a young adult, or a young adult and an elderly character.
 * Cap'n Bill and Trot in Frank Baum's Oz books. She's the daughter of his first mate from when he was a sailor, they now wander around Oz together.
 * Long John Silver and Jim Hawkins in Treasure Island, even more unusual when you consider that they spend at least half the book as antagonists. Silver is almost explicitly a replacement father figure. At least it explains why Jim, whose own father recently died, takes a liking to Silver despite having been warned about a one-legged pirate.
 * The friendship between Antonio and Ultima (not only old enough to be his grandmother, but also helped his mother birth him) is one of the central points of Bless Me, Ultima.
 * Harry Potter and Hagrid, Harry Potter and Sirius Black, Harry Potter and Dumbledore, Harry Potter and...
 * And Sirius Black is his godfather and closest tie to a father that he very much admires (and never really knew).
 * In The Lord of the Rings Bilbo is nearly 80 years older than Frodo, yet they have a very close relationship.
 * Other examples from the books (and films) include the several hundred years old Legolas and the 140 year old Gimli, and the friendship bordering on father-son relationship between Merry and King Théoden. However, one of the most prominent examples is the bond that forms between Gandalf (the "grandfather" of the Fellowship) and Pippin (the "baby" of the Fellowship) when they ride off to Minas Tirith together.
 * Frodo is in his 50s, a fully mature hobbit, whereas Merry and Pippin are still very young; Pippin is still in his Tweens. The Fellowship ages vary wildly, therefore they all sort of fit this trope.
 * Quite unexpected bonds fitting this trope are found in Conn Iggulden's Emperor series between Caesar/Brutus and Renius, the elderly gladiator who trained them and tried to kill them in their early teens. The bond between Caesar and Renius is founded almost immediately after the older tried to kill the younger, and lasts to the point where . The bond between Brutus and Renius is somewhat shakier at first, with the former vowing to kill the latter for what he did to Caesar. Though after traveling with Renius to Greece, Brutus comes to view him as the father he never knew. It is however unclear if Renius ever really feels any stronger bonds towards Brutus.
 * Another such bond in the series is between Caesar and Octavius.
 * Julius' friendship with Cabera. Caesar was all of 14 when he first meet Cabera, who was pushing eighty at the time, but is still strong and spry. When Cabera dies in the third book, it is close to twenty years later, though he had spent most of the decade-long campaign in Gaul partially disabled from a stroke suffered after using his quasi-magical healing gift on one of Julius' lieutenants.
 * In The Frog King, the main character Harry has a friendship with a homeless girl called Birdie.
 * Nearly every kids' novel written by John Bellairs features a relationship like this. Usually it is between a smart preteen who doesn't fit in with his/her peers and an eccentric elderly person who treats the kid like an equal, and they face the supernatural menace of the week together. Later on in each series, the kid usually brings in one or two new friends his/her own age who also become fast friends with the old person. Lewis Barnavelt had his Uncle Jonathan and Mrs. Zimmermann, who he introduced to Rose Rita Pottinger. Johnny Dixon had Professor Roderick Childermass, who he introduced to Fergy. Anthony Monday became friends with the elderly Miss Ells and her brother Emerson.
 * In Dan Abnett's Gaunt's Ghosts novel Armor of Contempt, Dalin Criid and Merrt are stuck in a training/punishment brigade and forge a friendship despite Dalin's being a new recruit, just old enough to join, and Merrt's being a battle-hardened soldier from the founding of the regiment. It continues in Only In Death. In Blood Pact, Merrt comes along to give Dalin moral support when he tells Hark about the twin.
 * Canadian teen novel Jack's Knife has a 14-year-old boy who lives with his overprotective mother, and an elderly man who served as a police officer and is also very knowledgeable about survival skills, as friends. The mother doesn't want her son hanging around this Cool Old Guy, and is completely against the relationship, always suspecting the worst.
 * A feature in the Haruki Murakami books The Wind-Up Bird Chronicle and Dance Dance Dance, both which feature a thirty-something year old man befriending a young teenage girl.
 * In The Dresden Files, Harry Dresden and the Archive develop into one of these.
 * In the Warrior Cats series apprentices almost always end up being good friends with their mentors.
 * Horace Harkness and Scotty Tremaine in Honorverse. A grizzled veteran, brawler and smuggler of a noncom, and a 20-year-old Ensign Newbie fresh out of Saganami Island in the first book. Twenty years and innumerable adventures later Master Chief Warrant Officer Horace Harkness and Captain Prescott Tremaine are still together, with  Horace Harkness even hacking the Navy personnel files just to be with his younger friend.
 * The un-named 20-something protagonist of Kokoro befriends a much, much older man whom he calls Sensei, as well as Sensei's wife.
 * Ted and Colin from Two Weeks With the Queen, who strike up a friendship over both having to deal with loved ones being seriously ill.
 * 14-year-old Blacky is friends with his elderly next-door neighbour Darcy in the books Deadly Unna? and Nukkin Ya.
 * In Great Expectations, Pip and Joe, his sister's husband.
 * From Where The Heart Is, Novalee, a teenaged girl, meets Sister Husband, a woman at least in her late thirties/forties. We also have Novalee and Lexie, the nurse who took care of Novalee after giving birth to Americus.
 * In The Book Thief, the girl Liesel (ranging from age 12 to 14) becomes friends with a Jewish man Max, who is twice of her age.
 * Beyond the Western Sea has Nathaniel (17) and Mr. O'Connell (50), also Maura O'Connell (15) and Mr. Drabble (30).
 * Sayuri and Mameha in Memoirs of a Geisha, who have a sisterly/mentor-like friendship between them.
 * In the Tiffany Aching sub-series of Discworld, Tiffany and Granny Weatherwax develop something along these lines, though Granny would probably be hard-pressed to admit it.
 * While most of the inhabitants of the magical worlds from Alice in Wonderland and Through the Looking Glass and What Alice Found There were pretty rude and dismissive of her, the White Knight temporarily befriended Alice, rescuing her from the Black Knight and escorting her to the end of the chess board. Some believe that the White Knight was Lewis Carroll's Author Avatar, given his own friendship with Alice Liddell.
 * Lawrence Block's detective character Matthew Scudder has a scrappy urban (read: black) 16-20-something kid following him around, and eventually helping him do things that a 60 something white guy can't get done. Matt even gives TJ his rent controlled apartment, in New York!
 * In Anne of Green Gables, Anne becomes friends with her best friend Diana's Great-Aunt Josephine, Mrs. Allan (the minister's wife), and her teacher Miss Stacy. In the sequel Anne of Avonlea, as a teacher she befriends her pupil Paul Irving, and Miss Lavender, who becomes Paul's stepmother. In Anne of Windy Poplars, she becomes friends with a young girl named Elizabeth, and in Anne's House of Dreams, she becomes friends with Captain Jim (who is in his seventies) and Miss Cornelia, who is fifty.
 * Most friendships in Twilight.
 * In Moses Man of the Mountain, Moses's two closest friends are his father-in-law Jethro, who is at least twenty years older than him, and his second-in-command and eventual successor Joshua, who is some forty years younger than him.
 * After the Quake. Landscape with flatiron. Junko, a girl past highschool-age and Miyake, a man in his mid-forties.
 * In Susan Cooper's King of Shadows, 11-year-old actor Nat is transported back in time to 1599, where he forms a loving friendship with 33-year-old William Shakespeare. Nat's father killed himself and Shakespeare's son died at Nat's age, which is why they are drawn to one another.
 * In There is a Happy Land by Keith Waterhouse, the 10-year-old Nameless Narrator becomes friendly with "Uncle Mad", a homeless, mentally simple adult man (implied to be at least in his thirties or forties.) Becomes crucial to the plot when
 * The Belgariad, by David Eddings: Most of Garion's friendships in the series are this, due to the fact that he is a teenager on a quest with a group of people who are all experienced warriors. Special mention should go to his friendship with Durnik (which formed before setting out on the quest, when Garion did have children his own age to play with) and with Silk (which was noted as being an especially close friendship compared to Garion's other relations).
 * Also, in The Elenium, there is Intergenerational Marriage between Sparhawk (the middle-aged Pandion knight, and the protagonist) and young queen Ehlana (on eighteen years old).
 * Diario de un Zombi has Erico (23) and Paula (8).
 * Mistborn. After joining Kelsier's oddball team of older men (most of them in their 30s at least), Vin (who is only 16) forms friendships with most, if not all of them.
 * Valkyrie and almost everyone else in Skulduggery Pleasant. With the exception of Fletcher, all her friends are 60-400 years older than she is.
 * In the Star Trek novel Paths of Disharmony, Eklanir th'Gahryn reflects on the value of these. In particular, his friendship with his much younger aide ch'Drena is highly important to him.
 * The relationship between the captured Russian officer Ivan Zhilin and his master's daughter Dina in Leo Tolstoy's short story A Prisoner of the Caucasus. Though the age difference was never specified, Zhilin was old enough to be married and Dina was stated to be about 13, this impliying a significant one.

Live Action TV
"Willow: This is Giles. He's our grown-up friend. Oh! Not like that."
 * The Doctor in Doctor Who is several centuries older than the majority of his companions. Even Romana, a Time Lady and his equal, was younger by about six hundred years.
 * Captain Jack Harkness in Torchwood is over a century older than the rest of the team
 * Sarah Jane Smith in The Sarah Jane Adventures is well into the Badass Grandma age range. Her closest friends are all teenagers.
 * Firefly has Badass Preacher Shepherd Book becoming unexpectedly good friends with Boisterous Bruiser Jayne.
 * By the end of Serenity, Mal and River.
 * Lex Luthor on Smallville started off friends with Clark, supposedly because Clark saved his life. He was around 9 when Clark landed in Smallville, which when Clark was a high school freshman would make him a 21 year old who's best friends with a 14 year old. The Dawson Casting keeps this fairly unnoticeable, as both actors are really in their 30s.
 * He started out as the Big Bad, but following his own Heel Face Turn and Lex's Face Heel Turn, Lionel Luthor did his best to become friends with Smallville's main cast, despite being somewhere in his fifties, while they were all in their teens. He manages to pull it off pretty well with regards to Clark and Chloe. Hawkman has this with Stargirl, Clark, and Oliver; Perry White has it with Lois.
 * Lost has Cool Old Guy Locke form a friendship with 10-year-old Walt that Michael did not like at all. Heck, if you want to get technical, seeing as Locke is the only Flight 815 passenger who is middle-aged (not counting side characters like Rose and Bernard), any friendship with him and another Lostie is an Intergenerational Friendship.
 * Star Trek: Deep Space Nine has a variation on this with the Dax symbiont being old friends with Benjamin Sisko, despite the symbiont being several times his age. Of course it helps when the symbiont is housed in such pretty bodies as Jadzia and Ezri.
 * That relationship falls into the traditional category as well. Dax's previous host, Kurzon, was significantly older than Sisko when they originally met and became friends. Kurzon's seniority is the reason Sisko calls Jadzia and Ezri "old man".
 * An episode in Star Trek: The Next Generation involving Data's relationship with a boy of about 10 or 11.
 * Data has another where he becomes "pen pals" with a young alien girl. Also, Wesley Crusher and the rest of the crew. At first, he's around 16, and many of the crew are twice as old as he is, sometimes older.
 * The friendship between Octavius and Vorenus + Pullo in Rome.
 * In Buffy, Giles begins as Buffy's Watcher but a deep friendship develops despite their many differences. This caused him to be sacked for having 'a father's love' for her. It also led evil werewolf catcher Cain to assume they were having a fling and make salacious remarks. They get rather angry at the insinuation.


 * And of course, used again in Angel. As a vampire, Angel is several hundred years older than those closest to him. Despite that, he ends up becoming best friends with Cordelia.
 * Forever Knight is very similar to that with Nick (800yrs old) and Natalie (just over 30)
 * Mick and Beth in Moonlight.
 * Duncan and Richie in Highlander the Series and probably Duncan and Methos to a lesser extent.
 * Ben (well over 1000 years old, appears to be about seventy) and Jenny (probably about nine-ish) in The Twilight Zone (original series), episode "The Fugitive".
 * Madison and JD on Harpers Island. Even though it mostly consisted of "hey watch me do bad stuff in front of you."
 * Omar and Butchie from The Wire: originally it looks like just a professional relationship, with the semi-retired Butchie as Omar's bank and the go-to man for third parties that want to contact him, but it becomes apparent that they have probably the closest relationship Omar has with anyone except possibly his grandmother.
 * In ER, Sam's son Alex strikes up a friendship with Dr. Kovac, perhaps trying to get him and his mother together.
 * Carol and her teenage lab partner when she's taking pre-med.
 * In an episode of Yes, Dear, Greg's 65 year old father has recently retired and gotten into Superman comics. He goes to a comic book convention and runs into his internet buddies, who are all no older than 12.
 * Steven Hyde and Leo in That '70s Show are a prime example of this. Aging 60's hippie meets teenage burnout.
 * Spencer and Sam on iCarly.
 * One episode of Being Human (UK) saw Mitchell befriending a boy who was their neighbor, protecting him from bullies and hanging out with him. The boy's mother is initially glad that he is being so nice, but things turn south when she catches the boy watching a vampire snuff film he got from Mitchell (Mitchell offered to loan the boy any of his Laurel and Hardy DVDs and forgot that he hid the snuff film in one of the cases). Cue accusations and a massive Paedo Hunt, which the boy tries desperately to put an end to.
 * Blair and Dorota on Gossip Girl.
 * In an episode of "Kate & Allie," Chip befriends Louis, a mentally handicapped and good-natured homeless man who appears to be the same age as his mother Allie. Kate and Allie initially hear Chip tell about his exploits with Louis and assume that Louis is another child, but later learn his true age when they find him in their house in the middle of the night after Chip invited him in so that he would have a place to sleep. Louis reappears in a few more episodes and his friendship with Chip continues.
 * Super Sentai has done this several times. Examples include Nozomu (10-11 years old) and Alata (21 years old, according to Word of God) in Tensou Sentai Goseiger; and Kou (9) and Lin (18) in Gosei Sentai Dairanger. The latter overlaps with May-December Romance since the show's epilogue implies they married or had a romance later on.
 * In an episode of Step by Step, we meet the twentysomething Cody's longtime best friend who's a middle aged man.
 * On The Young and The Restless, the rich and elderly Katherine is best friends with the decades younger former stripper Nikki.

Music

 * In "Cory's Coming" by Harry Chapin, a young man frequently visits Old John Joseph.
 * "Clair" by Gilbert O’Sullivan. He wrote the song about the young daughter of his then-manager, whom he often babysat. It’s actually a lot less creepy -- and more heartwarming -- than it sounds.

Video Games

 * In The Legend of Zelda: The Phantom Hourglass, while the fairy Ciela rightfully calls out 20s-30s Linebeck for being a coward, he seems to develop a real friendship with the twelve-year-old Link, even helping him save the world.
 * The Child Prodigy Sunny (eight years old) and the ever morally ambiguous medical worker Naomi (late thirties/early fourties) form something of a friendship in Metal Gear Solid 4: Guns of the Patriots.
 * BioWare and this trope are good friends:
 * Revan and Mission in Knights of the Old Republic (technically, Mission and everyone), as well as Jolee and everyone.
 * In Mass Effect, Shepard and Tali, and Shepard and Liara. In fact, for Liara and Shepard it is both ways. Liara is 106, the asari equivalent of being barely out of her teens, and Shepard is in his/her early thirties. Anderson and Shepard also are like this, with Anderson being 66 and in ME2 69.
 * Wrex from ME1 and Samara from ME2 (both roughly 1,000 years old) also count. The Shepard/Anderson friendship can also be interpreted as Anderson acting as a father figure to Shepard. Joker (late 20s/early 30s) and Dr Chakwas (late 50s/early 60s at the youngest) seems similar.
 * Alistair and Wynne of Dragon Age have a warm, somewhat flirty relationship with May-December subtext, though remains platonic.
 * Wynne also counts with Leliana and the Warden him/herself (who is usually stated as being relatively young). Though his age is not clear, Sten and the Warden may also count.
 * Kingdom Hearts. Sora's constant companions Donald Duck and Goofy are more or less adults, though this is a little obscured with them being anthropomorphic animals. Although his strongest feelings are for Riku and Kairi, who are his age.
 * The games also have a similiar friendship between Riku and Mickey.
 * And Axel's friendship with Roxas, as Axel is an adult and Roxas is in his early teens.
 * His relationship with Roxas and Xion is very like this in 358/2 Days, with the two both looking at Axel kinda like a big brother for his knowledge on the opposite sex, emotions, relationships... he in turn is very protective of them, and his anger at being forgotten makes a lot more sense considering this.
 * And again with Aqua, Ventus and Terra, which is all the more symbolic, considering the Theme Naming going on, and the fact that
 * Tales of Symphonia: Really depends on how you define "Intergenerational". The straight use of this comes with Lloyd (17) and Regal (33). But Lloyd is also good friends with Raine (23), Zelos (22) and his best friend is Genis (12). Kratos (27) doesn't really count seeing as he's
 * Zelos and Regal would count as well.
 * And to really screw with your head,
 * In Tales of the Abyss, this is pretty much true for Jade (mid-thirties) and the entire rest of the party, who are in their teens (except for Guy, who's in his early twenties). It's the most pronounced with Anise, who is thirteen and is frequently paired up with him when the party splits up in cutscenes and plot events.
 * Tales of Vesperia (noticing a theme here?) does this too; Karol (12) strikes up a good friendship with most of the party, but in particular his guild subordinate Yuri (21), who calls Karol 'Boss'. With one exception, none of the playable cast is over 21; that exception being Raven, who at 35 gets the somewhat sarcastic nickname "Old Man".
 * Several examples are possible in the Fire Emblem series, thanks to the support system. Among the more notable ones is Amelia (~15) and Duessel (old enough to be her grandfather) from The Sacred Stones, who even get a double-ending where Amelia becomes Duessel's "most trusted companion".
 * Also in Sacred Stones, Ewan (13-14) and his magic teacher Saleh (age not stated, but most likely in his mid to late 20's). They also get a double-ending.
 * In Princess Maker 2, the main character's daughter can have these dynamics with... a centuries-old dragon who lives the desert. The dragon is an old friend of the girl's father figure, back when he was a wandering warrior, and being a Chivalrous Pervert as well he endlessly teases the girl about her figure (and can give her the Dragon Tights, one of the outfits required for the dancing competition in the Harvest Festival).
 * Additionally, the dragon has a young and reckless grandson. If the heroine beats said grandson in battle when she's older than 15, the young dragon falls in love with her and the old one can give the main character the chance to have their kids engaged.
 * In Mother 3, almost all of the 10-year-old Lucas' party members are older than him. (OK, so Boney is a dog.) Kumatora's age is vague, but she seems to be in either her late teens or early twenties. Duster is in his 30s. All three of them depend on and trust each other.
 * For that matter, in Mother, the kids (well, the first two, anyway) befriend Teddy, a grown-up Gang Banger from Ellay.
 * Chopin and Polka in Eternal Sonata. They're so close that fans try to pair them together even though Polka's twenty-five years younger than him (and officially paired with Allegretto).
 * Felicia and Klonoa in Namco X Capcom are made of this. She is a Catwoman who's somewhere in her late teens or early 20s, while he is a Kaze no Neko ("Cat of the Wind") in his early to mid teens. Both of them are cheerful, positive and playful people who decided to be friends and stick together just because both of them are cat people with long hair.
 * Much for King's wall-banging dispair, they try to make him join their group, no matter how many times he tries to explain them that he's just a short-haired human Luchador wearing a jaguar mask.
 * Ace Attorney has quite a few examples, the biggest being Kay Faraday (17) and Dick Gumshoe (32), who end up acting like children when the other is around (they first met at 10 and 25, respectively). To an extent, Edgeworth (26) and Kay, Phoenix and Maya (24 and 17 when introduced), Nick and Pearl (9) and Gumshoe and Maggey (22) all count as well.
 * Also Machi and Lamiroir in Apollo Justice: Ace Attorney.
 * That one's more like a case of Parental Substitute.
 * The Judge. Who seems to develop, over time, an odd friendship with much of the main cast (especially Phoenix, as seen in Apollo Justice.) That doesn't stop him from giving you penalties though.
 * Professor Layton, especially in Professor Layton and the Unwound Future, features Layton and Luke's friendship. Unwound Future features a statue of a man with a top hat resembling Layton, and a young boy who looks like Luke, and the story on it describes a similar friendship between an author and a sick young boy until the boy died of his illness.
 * Sengoku Basara has several examples. There's Masamune (19) and Kojuro (30), who are sometimes joined by Itsuki (12); Yukimura (17) and Sasuke (23); Ieyasu (15) and Motochika (22); Yoshihiro (60s/70s) and Keiji (22); and Mitsunari (19/20) and Yoshitsugu (30s).
 * Yukari and Yuyuko in Touhou, the former several millenia-old at the very least and the latter (originally) an ordinary human. Even after Yuyuko has spent about a thousand years as a Cute Ghost Girl Yukari is still many times her age and outclasses her in every way possible, but they remain close friends.
 * Yukari also has a Vitriolic Best Buds-style relationship with Reimu, who still is human and whose age is a double-digit number. Frankly, most youkai with human friends are like this.
 * Kraden is friends with all of the player characters (most of whom are Kid Heroes) in the Golden Sun games. Piers may or may not be Really Seven Hundred Years Old, so his friendship with Felix's group likewise fits the mold-- in fact, he says that he'd rather not admit his age so it doesn't affect how they see him. Obaba becomes friends with the heroes of The Lost Age and Dark Dawn, as does her baby great-grandson Eoleo (on the younger end of the relationship in TLA, and the older end of the one in Dark Dawn).

Visual Novel

 * Narcissu ~ Side 2nd: Setsumi (15) and Himeko (23). The trope is invoked in this case, as Himeko was trying to finish the list of the 10 things that she wanted to do before her illness killed her, with one of the items being that she wanted to become friends with somebody significantly younger than herself.

Webcomics

 * Riff and Dr. Schlock from Sluggy Freelance (in their late 20's and late 80's, respectively) bond over their shared love of Mad Science.
 * Alcolla (preteen) and Yakuv (unspecified, but at least mid-30s) in Reliquary.
 * Julian Sands (adult camel) and Jarrad Dryandra (numbat child) in Doc Rat. Their friendship comes under scrutiny when.
 * Bob (probably in his twenties) and the elderly Mrs. Primrose in The Inexplicable Adventures of Bob.
 * Richard and Cale from Looking for Group. Richard is apparently hundreds of years old.
 * In Aki Chans Life (which is the sequel to the above mentioned fan fiction The Second Try) the titular Aki Ikari and former pilot Rei Ayanami are best friends, despite (or perhaps, because of) the big and weird differences in age between the two.
 * In Girl Genius, Agatha Heterodyne and the Jaegermonsters who follow her.

Western Animation

 * Essentially any cartoon in which a child and a cartoon animal are friends. The animals are often adult characters.
 * Avatar: The Last Airbender features three cases:
 * A strange friendship between Toph and Iroh before they realize they're both on opposite sides; Toph, who has joined the Gaang since they last saw Iroh, encounters him while having a brief falling-out with the others. And when they do realize they're on opposite sides,.
 * Aang and Monk Gyatso, which not only crossed generations, but incarnations as well: Gyatso was a friend of Avatar Roku, too. Though arguably, this was less a "friendship" as a case of Parental Substitute.
 * Aang and Bumi (a 12 year old boy and a man well over 100 respectively), though in this case they became friends while they were both kids (Human Popsicle complicates many things, except maybe friendship).
 * Joshua Jones features one of these between the 20-somthing title character and the 10 year old Ravi.
 * Pretty much all Transformer - human friendships are like this, due to the near-immortality of the Transformer race (bar accident or murder). It's slightly mediated in the sense that many of them (such as the Kid Appeal Character) have childish personalities.
 * This tends to happen amongst the robot characters as well, due to their extensive lifespans. The main cast of Transformers Animated includes Ratchet, who fought in the original war against the Decepticons, Prowl, old enough to have tried to dodge the draft, Optimus, Bumblebee, and Bulkhead, all relatively young, and Sari, who is eight.
 * Tintin and Captain Haddock. They fall in together during the derring do of The Crab With the Golden Claws and are constant companions from then on. It's difficult to determine when Tintin moves in with Haddock and Professor Calculus but it seems to be some time after the Moon adventure. The sheer oddness of their relationship has led to many snide remarks and speculation down the years, not least because neither are interested in women (the Captain's plain terrified), but theirs is a very sweet and lasting friendship where they continually lay down their lives for each other.
 * The Boondocks is rife with these:
 * Riley and Gangstalicious
 * Riley and Thugnificent
 * Riley and Ed Wuncler III, and Gin Rummy
 * Huey and Tom DuBois
 * Tom DuBois and Robert Freeman
 * Mac and Frankie from Foster's Home for Imaginary Friends, with Mac at 8 and Frankie at 22. Overlaps with a Precocious Crush on Mac's part.
 * In the Russian cartoon Smeshariki, there is a large number of intergenerational friendships since all nine cast members are friends and are of different ages (it can be inferred from their manner of speech, interests and mannerisms that 2 are seniors, 3 are middle-aged and 4 are youngsters).
 * Bart and Otto from The Simpsons.
 * And certainly Lisa and the late great Bleeding Gums Murphy.
 * Freakazoid and Sergeant Cosgrove. There was even a Running Gag involving Sergeant Cosgrove pulling up to Freakazoid in his car and asking him if he wants to do something together like bumper cars.
 * Jade and Torhu of Jackie Chan Adventures. Many times, Jade would ride the much larger Torhu on his shoulder. She even gave him half of a yin yang necklace to show their bond.
 * Chowder and Gazpacho from Chowder.
 * Mary and Max, from the film of the same name, a lonely nine year old girl in Australia and a 44 year old man with Aspergers Syndrome in New York.
 * Jonny and Race from Jonny Quest have more of a father/son dynamic; however, in one episode of Real Adventures, Race says that Jonny is his new best friend. Jonny's 13/14 and Race is in his late thirties.
 * He-Man and Duncan in He-Man and the Masters of the Universe. Take into account that Duncan is also He-Man's father's advisor/best friend and He-Man's main love interest is Duncan's daughter Teela.
 * The title character of Word Girl was once good friends with Steven Boxlitner who was much older than herself. Even though Steven is now Two brains Wordgirls still has some sort of Friendship with him.
 * Terry McGinnis and Bruce Wayne in Batman Beyond.
 * Lydia and Beetlejuice in the Animated Adaptation. The 12 year old befriends the several hundred year old Jerkass.
 * In Adventure Time pilot Finn is twelve and Jake is twenty-eight, while in the series Finn is 13 and Word of God specifying Jake is twenty-eight in "magical dog years"--which could possibly make him younger than Fin in absolute terms but he's certainly of adult age for his species. They're also adoptive brothers, Finn having been raised by Jake's parents.
 * Technically Finn and Marceline, since she's Really One Thousand Years Old (though she looks more like a teenager or young adult).
 * Noodle with all her bandmates from the Gorillaz. At least, they're all clearly more attached to her than to each other.
 * Kim Possible and Shego ("Stop Team Go"), Shego and Drakken (sometimes).
 * Recess: Spinelli, who's nine, and Miss Grotke, who's implied to be in her early 30s. Because of this, Spinelli looks up to her like a mother figure (as Spinelli's real mom embaresses her to extreme levels and forces her into girly activities, which she hates). It's adorable.
 * In Sonic the Hedgehog it's most of the Freedom Fighters and Sir Charles "Uncle Chuck" Hedgehog. Of course, it's most because his nephew is the show's star. The same could also be said with Tails and the rest of the Freedom Fighters.
 * In Transformers Prime, the Autobots are much older than their human allies, who have an age range from 12 to 16.
 * Apple Bloom and Zecora in My Little Pony Friendship Is Magic.

Real Life

 * The ancient Greeks used to practice Pederasty, which was an older male looking after a younger male. Quite often there was more to it but the original intents and purposes of the arrangement was so that an older person can pass on his wisdom to a younger generation.
 * A similar practice called shudo went on in ancient Japan.
 * Message boards, online games and other websites where people who share a common interest gather. Sports, video games, politics and TV shows are just a few of the subjects that can provide common ground for people who become close friends long before they even learn each other's relative age.
 * Or gender, race, or religion. The internet has a lot of problems, but damn if it doesn't bring us together.
 * Although usually you can tell if they're really young by how often they toss racial slurs at you.
 * You can also guess a person's age by their reaction to losing and winning, the trend is that the younger a person is, the more fixated he is on winning and the more bitching he produces when losing.
 * Common among socially awkward or shy individuals. Making friends with someone much younger or older is often easier because someone from a different generation won't be held up to as high a social standard. For example, a teenager might reject another teenager for being a Star Trek fanatic, but a thirty-year-old probably wouldn't... A ten-year-old might be rejected by her peers for being painfully shy; but chances are the kindergarteners think she's pretty hot stuff. A 5 year old might not be the envy of his similarly aged peers; but to 7-12 year olds he's either adorkable or just plain cool. Etc.
 * Dame Margot Fonteyn and Rudolf Nureyev. Best friends, best ballet partners... and she was 19 years older than him. In fact, Dame Fonteyn was about to retire when they started dancing together, but then she decided otherwise and they were a ballet duo for fifteen years.
 * Lady Gaga and Cyndi Lauper. Despite their age difference of 32 years, they get along very well; Gaga considers Cyndi to be a Cool Big Sis figure, and Cyndi feels as though she can be as weird as she likes when she's with Gaga.
 * Michael Jackson and either Dame Elizabeth Taylor (difference of 26 years) or Diana Ross (14 years).
 * Most workplaces in general can end up being this.
 * Animal example: A baby hippopotamus that was rescued after floods in Kenya made news everywhere when it befriended a 100-year old tortoise in a wildlife sanctuary.
 * Also, a 47-year-old gorilla and a much younger rabbit.