History Main / LongLostUncleAesop

* Intended, but then subverted, with the character of Velvet in ''Franchise/{{RWBY}}''. Her original function in Volume 1 was to simply give a face to the concept of [[FantasticDiscrimination anti-Faunus discrimination]], but she proved so popular almost instantly that she returned in Volumes 2 and 3 as a supporting character, and her team later received [[Literature/RWBYAfterTheFall a tie-in novel]] after Volume 6.

* The TonightSomeoneDies episode of ''WesternAnimation/CloneHigh'' introduced - and killed - Ponce de Leon (portrayed as The Fonz and voiced by Luke Perry) as JFK's inseparable best friend, despite the fact that JFK was the main character who had already appeared extensively. Considering this is ''Clone High'', however, this was the joke to begin with: the opening narration even promised a main character would die and went on to [[SuspiciouslySpecificDenial specifically insist this wasn't "that thing were they introduce a character only to die"]] while [[RefugeInAudacity repeatedly showing images of the as-of-yet unintroduced Ponce]].

* ''WesternAnimation/TeenTitans'' had one, an alien named Val-Yor in the episode "TROQ". He comes to Earth to enlist the Titans to help him defeat some evil robotic aliens who, according to him, want to wipe all organic life. Unfortunately, he turns out to be a [[FantasticRacism racist jerk]] who treats Starfire with contempt due to her species, calling her by the slur [[TitleDrop "Troq"]] , meaning "nothing" in her language. The rest of the Titans eventually find out about this and swiftly turn on Val-Yor. An aesop is dispensed about how being racist is bad and that some people will never change, and Val-Yor is never seen or heard from again after taking off back into space.

** In "Killed By Death", Buffy exhibits a phobic reaction to being in the hospital, and we learn that it's because of her cousin Celia's death when they were kids. They were close, and Buffy was traumatized as a result of watching her die. While some of this trauma is legitimately resolved in the episode, the lack of mention of Celia before or after makes the whole thing seem to come out of nowhere. It is particularly jarring because Buffy spends a great deal of time visiting the hospital in Season Five, and shows no phobia beyond an appropriate reaction to the immediate circumstances. Nor does the First Evil ever manifest in Celia's form, which would seem an obvious way to get under Buffy's skin if the writers still remembered the character. Granted, the actress playing Celia - a long-deceased ''child'' character - could not conceivably return, since the First Evil was only prominent ''five years later''. It might've worked in the Season 3 episode "Amends", but then the First was focusing more on Angel than Buffy.

*** Aunt Margaritte does show up in the time-travel episode, though.

** Fluttershy's brother shows up in one episode to teach the class "Don't be a freeloading tool" and promptly vanishes back into the void. Oddly, when he does appear in a later episode he's been reduced to ComicRelief and his genuine (if poor) attempt at holding down a job isn't enough to keep him from being fired.

* The ''WesternAnimation/{{Arthur}}'' episode "So Long, Spanky" showed that D.W. having a pet bird, whose only role in the episode was to [[DeathIsASadThing be part of an Aesop about death]].

* A staple of the YA girls' series popular in the 1990s -- not surprising, considering these books were sitcom episodes in print form. A typical example from ''Literature/TheBabySittersClub'' series: Amelia, suddenly introduced as a close friend of Mary Anne, was never been mentioned before the book in which she's killed by a drunk driver to teach the moral of the story. The ''BSC'' used this a lot. A new baby-sitting client would be introduced at the beginning of the book, needing the services of the club, and naturally after a few sitting jobs the girls would realize something was up. The most pointed examples are ''Keep Out, Claudia!'', dealing with a mother whose super-Aryanism would be comical if it wasn't so disconcerting, and ''Claudia and the Terrible Truth'', where the girls learn that two boys are being physically abused by their father. The latter is [[NightmareFuel one of the creepiest books in the entire series.]]

* ''Series/TwoAndAHalfMen'' has an episode about Charlie's best friend (played by Charlie Sheen's real life brother) dying from having a similar lifestyle to his. What's interesting is that said best friend had never been mentioned before and was never mentioned again. In fact, Alan didn't even know him in spite of having lived at Charlie's house for quite some time by then.

* ''Series/BuffyTheVampireSlayer'':
** In the episode "Lie To Me" from season two, there is Ford, Buffy's "best friend" from her old high school in L.A. Ford is dying of a brain tumor, and bargains with Spike to be turned into a vampire in exchange for Buffy. Justified in that Buffy had moved a year ago, presumably leaving some her friends behind, and she'd spent the summer break back there, offscreen.
** In "Killed By Death", Buffy exhibits a phobic reaction to being in the hospital, and we learn that it's because of her cousin Celia's death when they were kids. They were close, and Buffy was traumatized as a result of watching her die. While some of this trauma is legitimately resolved in the episode, the lack of mention of Celia before or after makes the whole thing seem to come out of nowhere. It is particularly jarring because Buffy spends a great deal of time visiting the hospital in Season Five, and shows no phobia beyond an appropriate reaction to the immediate circumstances. Nor does the First Evil ever manifest in Celia's form, which would seem an obvious way to get under Buffy's skin if the writers still remembered the character. Granted, the actress playing Celia - a long-deceased ''child'' character - could not conceivably return, since the First Evil was only prominent ''five years later''. It might've worked in the Season 3 episode "Amends", but then the First was focusing more on Angel than Buffy.
** ''Buffy'' subverts this in the episode "The Puppet Show," however. When Emily (the dancer) is killed, Cordelia claims that she has lost "like, my best friend" - although Emily had never been mentioned on the show before. A subversion because Cordelia refers to Emily incorrectly as "Emma" during this speech and Xander calls her on never really having known the girl.

** The Janitor likes to plays with this trope. In one episode he puts on a fake mustache and denim jacket and tries to convince everyone that he is his own twin brother (nobody buys it); in another he pretends a nearby child is his son to make J.D. feel bad about insulting him. In a third he mentions his father died, causing J.D. to call him out by pointing out that he had met his father in a previous episode; the Janitor merely responds that "you met a man".

* ''Series/MightyMorphinPowerRangers'' did this sort of thing a lot. One episode featured Kimberly's friend who's deaf (revealing that the Pink Ranger knows Sign Language in the process), appearing just in time to be immune to a music-related MonsterOfTheWeek's powers, while dropping an Aesop on being nice to people with disabilities. One could argue that the girl could be a friend from school, but she still came out of the blue.
* ''Series/FullHouse'':
** Uncle Jesse's grandfather, referred to as "Papouli"[[note]]which is an informal version of "Grandpa" in Greek[[/note]], came from Greece to visit and have fun with everybody, then died about midway through the episode. They mourned, the VerySpecialEpisode taught us how to cope with old people dying, and Papouli was never mentioned again. To be fair, this was his second appearance on the show. The Greek relatives visited in an early season episode.
** Also, the episode about Stephanie's classmate that gets beaten. Jesse makes some calls, the kid's removed from his home, and he's never mentioned again.
* in ''Series/RobinHood'', we learn (for the first time) in the fourth-to-last episode of the ''entire show'' that Robin's never-before-mentioned father and Guy's never-before-mentioned parents were all killed together in a fire. Except that Robin's father Malcolm ''didn't'' die, and he's actually been wandering Sherwood all this time without ever bothering to help or get in contact with his own sons or the two orphaned children of the women he loved. He reappears to tell Robin and Guy that they need to work together in order to rescue their mutual half-brother Archer.
* ''Series/TheGeorgeLopezShow'' did this often with guest stars, especially with Carmen's friends and boyfriends, examples including Carmen's boyfriend of one episode with an {{Aesop}} about being pressured into sex and Carmen's best friend of one episode telling her about the trend of wearing different colored bracelets to symbolize different places you had sex.
* Lucy's friend Sarah in the ''Series/SeventhHeaven'' episode "Nothing Endures but Change" had never been seen or even mentioned before the episode. (However, she did get a mention three seasons later, by Lucy herself while she acted as grief counselor to her friend Mike and his shell-shocked mother.)
* In the ''Series/{{Glee}}'' episode "Laryngitis", when Rachel loses her voice, Finn takes her to meet a quadriplegic friend of his who became paralyzed after an accident playing football. His Aesop was that he lost his ability to do what he loves most, but is working around that in order to live a fulfilling life. What makes this example particularly bad is that ''Glee'' is known for keeping track of its recurring characters, no matter how minor.
* Nathan Kress played one of these -- a wheelchair-bound accident victim -- on ''Series/TheSuiteLifeOfZackAndCody''.
* ''Series/TheSecretLifeOfTheAmericanTeenager'' had Ricky's never-mentioned former foster brother Ethan show up so the show could have a very special episode about sexting.
* In one VerySpecialEpisode of ''Series/BoyMeetsWorld'', Shawn and Cory help protect a classmate who is being physically abused by her dad, and at the end of the episode she is sent to live with her aunt in another state. This girl was never seen before this episode and is never mentioned again.
* A first season episode of ''Series/DawsonsCreek'' featured a character named Mary-Beth who was supposedly a friend of Dawson's with a crush on him.
* In one episode of ''Series/SavedByTheBell'', Zack learned a valuable lesson about his Native American heritage (which is never discussed on any other episodes) from a man named Chief Henry, who promptly died at the end of act 2, allowing Zack to learn yet another valuable lesson about losing loved ones.
* The "She's Positive" episode of ''Series/TheParkers'' had T meet the girl of his dreams, but finds out that she is HIV positive. At the end, they decide to continue their relationship but to take it one day at a time. The girl is never seen or mentioned again.
* In the ''Series/CriminalMinds'' episode "The Fallen", we meet David Rossi's old Vietnam sergeant who had a profound effect on Rossi's life (despite the fact that Rossi never mentioned him before this episode, and he'd been on the team at this point for five years), and whose sole existence in the episode is to provide the underlying message of "[[StrawCivilian support our troops at all costs]]". It's justified in the fact that the sergeant fell off the grid after becoming homeless.
* Done several times in ''Series/{{Hollyoaks}}''. One the best-remembered examples is when Hannah Ashworth went to a treatment facility for her anorexia and befriended a fellow patient named Melissa, who subsequently died from her illness (prompting Hannah to want to get better.) A very similar storyline took place when Jason Roscoe goes into a clinic for his body dysmorphia and is encouraged by a new friend to take diet pills... then the friend dies from abusing the pills.

* An episode of ''Series/MrBelvedere'' revolves around Wesley's best friend Danny, who never appeared in previous episodes, having AIDS. After misconceptions about AIDS are cleared up and Wesley reconciles with Danny, he is never seen again.
* ''Series/TheFreshPrinceOfBelAir'';
** One episode has a young man appear claiming to be Geoffrey's illegitimate son. When Will catches him stealing money, he doesn't want to tell Geoffrey for fear of upsetting him. When Geoffrey does find out, he forgives his son because that's what family does. The episode ends with them hugging and his son leaving. In the series finale, Geoffrey moves back to England to be with him.
** Another episode has Will's DisappearedDad coming back. It ends with him abandoning Will again and Will angrily declaring that he's done with him.
* ''Series/{{Elementary}}'': In the final season, the 11th Precinct is temporarily led for a few episodes [[spoiler:after Captain Gregson is shot and seriously injured]] by a Captain Dwyer, who is supposedly an old buddy of Gregson but has never appeared or been mentioned before. After Gregson returns, he discovers that one of his top female officers (who has also never appeared or been mentioned before) is leaving the force due to being sexually harassed by Dwyer. Both characters are then used for a slightly heavy-handed single-episode subplot about the evils of sexual harassment.

* ''WesternAnimation/ElChavoAnimado'' has Rosita in the episode "El valor de la amistad" (The value of friendship). She only appears to fix the children's friendship and teach them to forgive. [[spoiler: It is hinted that she is a magical being at the end of the episode, as she transforms into a flying magical sphere.]].

[[folder:Film]]
* ''Film/SpiceWorld'' brings in a pregnant best friend for the Music/SpiceGirls, Nicola, so that the girls can ponder the lessons of maternity without actually experiencing it.

** [[spoiler:Subverted with]] Bismuth, who initially shows up in her eponymous episode as one of these, a WellIntentionedExtremist to teach Steven the perils of [[ThouShaltNotKill using shattering as a solution to evil]]. [[spoiler:She [[HeelFaceTurn eventually comes around]] in a later episode, and rejoins the Crystal Gems permanently in time for the finale, movie, and SequelSeries.]]

* ''WesternAnimation/StevenUniverse'': Parodied in "Say Uncle", when WesternAnimation/UncleGrandpa shows up in Beach City in a crossover episode, helping Steven learn to show him how to summon his shield as an EccentricMentor who uses rocket launchers, snakes, bees, and vaporizers to help Steven's shield which Uncle Grandpa erroneously believes to emerge whenever Steven's in danger. Mr. Gus, who has an extensive knowledge of magical beings, sets Uncle Grandpa straight by telling him that Steven's gem shield summoning is based on emotional clarity. When the Gems attack U.G., Steven, who has learned more about summoning his shield by defending U.G., tells them that they can't attack people just because you don't understand them, and that you should take time to listen to what the other person has to say.

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** It happens with their families too. Carla's brother has the distinction of lasting most of a season, but afterwards is never heard from again, not even to meet his baby niece; her sisters only make cameo appearances in a couple of episodes. Turk's brother gets one episode, and phones Turk in another confirming that he can make Turk's wedding (though as far as the audience can see, he doesn't). Their families do get mentions, but they seem to miss nearly every important occasion. Averted with J.D.'s brother Dan, who is a semi-recurring character, and Elliot's parents, who are mentioned frequently and appear on occasion. Justified with J.D.'s father, who was respectfully killed off thanks to ActorExistenceFailure, and Doctor Cox's sister, whom he simply doesn't like to talk about as she reminds him of their painful, abusive childhood. Also justified with Jordan's sister Dani, who was a recurring supporting character but vanished from the last seasons; this was mostly in-character.

** Uncle Jesse's grandfather, refered to as "Papouli"[[note]]which is an informal version of "Grandpa" in Greek[[/note]], came from Greece to visit and have fun with everybody, then died about midway through the episode. They mourned, the VerySpecialEpisode taught us how to cope with old people dying, and Papouli was never mentioned again. To be fair, this was his second appearance on the show. The Greek relatives visited in an early season episodes.

-->'''Rainbow Dash:''' ''Not'' cool.

* The BBC once did a week of shows covering domestic violence and asked ''{{Series/Neighbours}}'' to include an appropriate storyline that week. The result: Boyd Hoyland's rarely seen friend Daniel Clohesy reveals that his never-before-seen father has hit him.

* ''Series/{{That 70s Show}}'' episode "Eric's Buddy" featured a new gay character. Even though he and Eric became good friends during the episode, he was never seen or referenced again.