Finding out parentage in a story can be shocking to characters, but so is finding out they are a parent. A character comes along, and suddenly turns out to be either a [[LongLostRelative long lost child]], or a child a character never knew he had ([[MamasBabyPapasMaybe since it has to be a guy]] unless RuleOfFunny or AppliedPhlebotinum comes into play). This is what you get when a MissingMom or DisappearedDad had no idea they were one in the first place.

This is of course the flip-side of LukeIAmYourFather. Compare SeparatedAtBirth, LukeIMightBeYourFather. May result in SinkOrSwimFatherhood. Subtrope of ConnectedAllAlong. This is a Reveal Trope, so '''Spoilers''' will be coming your way.

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!Examples:

[[foldercontrol]]

[[folder:Anime & Manga]]
* ''Manga/SoltyRei'' Roy Revant's daughter Rita Revant [[spoiler:turns out to be Rose Anderson. Her hair and eye colour had changed due to exposure to nanomachines from the Blast Fall. Having been adopted by Larry and Andy's father with no memory of who she was, she initially resisted the idea that she was Roy's daughter until later.]]
* ''AngelSanctuary''. Angels aren't allowed to have children, so Zaphikel [[spoiler:is tricked into killing his pregnant lover and]] brings his child's fetus to the breeding machine, to make it pass for a legal, artificially made angel. He's too late, the fetus is dead, so he tries to kill himself. Then Adam Kadmon shows up and saves him, but the sight of such a glorious creature leaves him blind. Years later, Adam Kadmon shows again and restores his sight, he takes a glimpse at his then asistant, Raziel, and instantly realizes that he is his son, Adam Kadmon had resurrected him back then and ''he didn't notice because he was blind''. [[spoiler:Then he dies.]]
* The entire premise of ''OtakuNoMusumeSan'', where Kouta first learns he has a daughter, Kanau, when she shows up on his doorstep, with a note from her mother reminding him of a certain eventful afternoon about ten years before. Eventually it starts turning out that [[EveryoneIsRelated everyone is "related"]], too (mostly through things like adoption, [[spoiler:marriage]], and friendship), though it's one case that's not much connected to this trope.
* ''Manga/JoJosBizarreAdventure'' does this three times: Josuke, the protagonist of part 4, is part 2 hero Joseph's long-lost son. Giorno Giovanna, protagonist of part 5, is the son of [[BigBad Dio Brando]], and in part 6 we meet Dio's other sons.
* ''[[DragonBall DBZ]]'' -- Trunks, anyone? Techincally he's a KidFromTheFuture and Vegeta only found out their relationship after the Trunks of his timeline was born.
-->'''Vegeta''': Wha-? "Trunks"? How bizarre, [[CaptainObvious he has the same name as my son]]. Wait a second, a Super Saiyan from the future? Of course, it has to be! He's ''my'' son! Unbelievable!
* The true BigBad of the ''Anime/{{X-Men}}'' anime is revealed in episode 12 to be [[spoiler:Professor Xavier's crazy RealityWarper son Takeo. Takeo's mother had told Xavier that his son was dead.]]
* In ''Manga/FairyTail'', Cana's motivation for passing the S-class exam is so she can work up the nerve to tell [[spoiler:Gildarts]] that she is his daughter.
* In ''Manga/MahouSenseiNegima'', the main antagonist of the Festival Arc is [[spoiler: Chao Lingshen]], who is eventually revealed to be [[KidFromTheFuture a descendent of Negi's from 50 years in the future.]]
* Subverted in SDGundamForce. While Kibaomaru learns that [[spoiler: Genkimaru is his son]] from Shute, he doesn't believe it until he remembers the OrphansPlotTrinket.
-->'''Kibaomaru:''' That's why he had the dagger with my emblem...the one I gave to that woman...
[[/folder]]

[[folder:Comics]]
* Connor Hawke, the second GreenArrow, showed up in the '90s as the son the first Green Arrow, Ollie Queen, never knew he had. [[RetCon Retcons]] have since established that Oliver actually did know, and Connor knew Oliver knew, although [[IKnowYouKnowIKnow Oliver didn't know that Connor knew Oliver knew]]. All clear?
* Professor X was shocked to discover in ''NewMutants'' #26-#28 (published 23 years after his first appearance) that he had a son in the extremely powerful mutant Legion aka David Charles Haller. Up until then he had assumed David to be the son of a dead friend.
* {{Wolverine}} turned out to have both a gender-swapped clone (Laura Kinney, aka ComicBook/{{X 23}}), ''and'' a long-lost son, {{Daken}}. Hell he's even come across ''an entire team'' of his children sent to kill him that he didn't know about until after the fact.
* The new Scorpion is the daughter of villainess Monica Rappaccini, probably fathered by [[Comicbook/IncredibleHulk Bruce Banner (aka the Hulk)]]. Speaking of the Hulk, he also has his son Skaar, who was still in his mother's womb when she died, as well as Lyra, his daughter by Thundra from a divergent future. There's also Skaar's twin, Hiro-Kala.
* [[LampshadeHanging Semi-Lampshaded]] in the newspaper comic strip ''FoxTrot'', in which young nerd Jason campaigns for Lucasfilm to digitally insert him into the Special-Edition StarWars films as Luke's younger brother. Obviously, this goes nowhere. ("At least they sent back my Darth Jason prototype action figure.")
** [[HilariousInHindsight Darth Jason?]]
* Wildcat IV in ''JusticeSocietyOfAmerica''.
** The JSA has a bit of a habit of this. Jade and Obsidian pulled this one on Green Lantern (Alan Scott) when they were first introduced back in TheEighties.
* Captain Boomerang II in ''ComicBook/IdentityCrisis''. Includes the literal line, as when Captain Boomerang tracked down his son, put up for adoption, he lost his nerve at the last moment -- too late to prevent his son from seeing him and making the jump.
* The Trickster in the DC Universe once went to help an ex-girlfriend whose son was in danger. After protecting him from the demonic Neron, he did the arithmetic to realize who the father had to be.
* Darkdevil in ''[[Comicbook/SpiderGirl Spider-Girl]]'', who is revealed to the reader - but not the heroine or her family, yet - to be the son of Ben Reilly, Spider-Man's clone.
* In the new BoosterGold comics in which Rip Hunter, a character first introduced in the DCU in the 1950's, bullies Booster into being an unknown hero, there've been strong hints that [[spoiler: Rip is Booster's son. [[KidFromTheFuture From the future]].]] Try not to think about causality too hard. Booster himself also crashes at his great-great-great-etc grandfather's house.
* Tossed in a blender with LukeIAmYourFather (but not really) in ''UsagiYojimbo'': [[spoiler: Usagi discovered that his old flame Mariko's son Jotaro is actually ''his'' son, and Mariko's husband (Usagi's ''very'' unfriendly rival) also knows but loves Jotaro anyway. Usagi and Jotaro's sword master guessed almost immediately (they're very much alike), and gives them the opportunity to travel together for several months; after talking with Tomoe about responsibilities and relationships, Usagi decides not to break the bond between Jotaro and his family, while ''Jotaro'' decides not to force Usagi to give up his wanderer lifestyle to take care of him. It turns out Mariko told Jotaro the truth, but left out the part about Usagi knowing too. Upset at his "weakness" and the fact that he doesn't know when or if he'll ever see his "uncle" again, Jotaro calls out "Miyamoto Usagi! You are my father!!" but Usagi is already too far away to hear ("Just a trick of the wind, I must be tying my ears too tight").]] TL;DR: Father A and Son B know the truth, but each doesn't know the other knows the truth (C,D,E, and F know the truth too, but they aren't talking, mainly out of respect).
* In ''GreenLantern Corps'' #35, it's revealed that [[spoiler:Korugarian Green Lantern Soranik Natu]] is {{Sinestro}}'s daughter.
* In "The Long Cold Dark" story arc of ''Comicbook/ThePunisherMAX'', Frank Castle discovers that [[spoiler: Kathryn O'Brien gave birth to his daughter before she died]]. [[spoiler: His recurring foe Barracuda kidnapped her to get to him]]. Needless to say, [[PapaWolf Frank was pissed]].
* During the "Salvation" [[StoryArc arc]] or ''Comicbook/{{Preacher}}'' Jesse becomes acquainted with a woman named Jodie, whose demeanor and appearance bears an uncanny resemblance to the deceased Jody from previous arc "All in the Family." Jesse begins to feel that something is amiss about Jodie beyond the obvious the more time he spends with her, until it finally hits him one night while alone with her in her bar and he can only say one word: [[spoiler: Mom?]]
* In ''Franchise/{{Batman}}'', Damian Wayne, son of Bruce Wayne and Talia al-Ghul, was raised in the League of Shadows since birth with his father never knowing about him until years later.
** He made his grand entrance by beating the shit out of Tim Drake, the current Robin, in the apparent belief this would make him Robin. (Jason Todd expressed his return to life by beating up Tim. Tim is kind of the ButtMonkey of the batfamily, which is saying something since Jason got killed and Barbara crippled.)
** Damian was retconned into being a ChildOfRape via Talia drugging Bruce, and then, by the way, she put him into an ArtificialWomb as soon as possible so being pregnant wouldn't have the chance to ruin her body. (It often does that and she's put everything into her physical prowess.) This comes up when it turns out she's given him up as corrupted by Batman's ethics and is replacing him with a clone.
* In ''YoungAvengers'' Presents: Hulkling, Hulkling does this to [[spoiler: Captain Marvel. Who turned out to be a Skrull anyway. Awkward.]]
** [[spoiler: Wanda and Billy, in ComicBook/TheChildrensCrusade, because Wanda has lost all her memories.]]
[[/folder]]

[[folder:Fairy Tales]]
* In ''[[http://www.mythfolklore.net/andrewlang/185.htm The False Prince And The True]]'', a young man on trial for his life after striking [[RoyalBlood the prince]] reveals at the trial that the queen had actually passed off a quarryman's son as hers, and the king's, while he himself was the offspring of the king by a secret marriage.
[[/folder]]

[[folder:Fan Fic]]
* When Asa in ''FanFic/FutariWaPrettyCureBlueMoon'' first starts to wonder about EnigmaticMinion Mekuramast's true motives, her initial conclusion is that he's her DisappearedDad, and she confronts him about this. As this theory is purely born of Asa's WrongGenreSavvy and, more to the point, makes no sense, it's quickly refuted, and he spends the rest of the story thinking she's a nutcase.
* Day 1 of ''Fanfic/{{One Hundred Days|BuzzLightyear}}'' has Warp Darkmatter telling unmarried and ''virginal'' Buzz Lightyear and Mira Nova that they're his parents, and he has proof to boot. Turns out, he's right!
* ''Who Is Voldemorts Dad? The Tales of Vernon Dursly!'' by the infamous [[DarkAndLightTheAdventuresOfDarkYagami D'arkYagam'i]] is exactly what the title implies
* ''{{Series/Emergency}}'': John Gage finds out in "[[http://audreys-efanfic.freeservers.com/lostandfound.html Lost and Found]]" that his girlfriend had his child while he was being held captive and gave her to Roy and Joanne. They begin raising her as theirs, and when John is found alive and brought home, Roy has such a hard time figuring out how to tell John that he figures it out himself when he sees his mementos and pictures in the baby's room.
[[/folder]]

[[folder:Films -- Animated]]
* [[spoiler: Cornelius "Lewis" Robinson]] to Wilbur from ''Disney/MeetTheRobinsons''.
* ''Disney/AladdinAndTheKingOfThieves'': Happens when Aladdin meets his father Cassim. Cassim is convinced by the dagger Aladdin is carrying - he had left it with his wife to give to their son when he was old enough.
[[/folder]]

[[folder:Films -- Live-Action]]
* ''Film/ForrestGump'' finds out he has a son via Jenny. EpilepticTrees say this might not be the case, but Forrest is the only reliable parent Jenny can find.
* ''Film/{{Wasabi}}'': Jean Reno's character discovers he has a Japanese daughter.
* ''Film/KillBill'''s TwistEnding, in which Beatrix Kiddo discovers that [[spoiler: her daughter is still alive]].
* ''Un Indien dans la Ville'', and its English-language remake, ''Jungle2Jungle''.
* As IndianaJones and Marion Ravenwood are sinking into sand in ''Film/IndianaJonesAndTheKingdomOfTheCrystalSkull'', [[spoiler:she reveals Mutt Williams is his son. HilarityEnsues.]] It's ''also'' LukeIAmYourFather at the same time.
* In ''TheLongKissGoodnight'', the BigBad is about to leave Charlie and her young daughter to freeze to death in a meat locker. Charlie, in an attempt to save her daughter, reveals to him that her daughter is also his daughter. He leaves them both in the locker anyway.
* ''{{Oldboy}}'' features a particularly cruel example: the main character is the victim of an elaborate revenge/imprisonment plot, the final result of which leads him to discover that [[spoiler: the young woman he fell in love with and just had sex with is his long-lost daughter. TheReveal had such a big impact on him that he cut off his own tongue and went to hypnotist so he could forget]]. The villain really out-did himself with his revenge.
* TheReveal in the slasher film ''Film/CherryFalls''. The SerialKiller targeting virgins [[spoiler: Marliston]] is strongly implied to be [[spoiler: the son of Sheriff Brent [[ChildByRape conceived through rape]] 25 years ago, making him the protagonist Jody's older half brother.]]
* [[Film/TronLegacy "Dad?"]]
** [[AvertedTrope "I'm not your father, Sam...]] but I'm very, very happy to see you."
* The main plot of ''Film/MatchstickMen'' revolves around this. [[spoiler: It's actually a con, though.]]
* ''Literature/ADogOfFlanders'' -- Nello tells [[spoiler:Michel]] that he's Nello's father.
* There's one implied at the end of ''Dream Girls'', when Magic finally meets his father, who is understandably quite shocked by this revelation.
* In ''Film/{{Beowulf}}'', the Dragon reveals to Beowulf that he is actually the hero's long-lost son from his deal-with-the-devil dalliance with Grendel's Mother.
* {{Parodied}} in ''Jane Austen's Mafia!'', when a woman meets a young boy at a party.
-->'''Diane:''' So, what's your name?
-->'''Boy:''' Diane.
-->'''Diane:''' Like me!
-->'''Anthony:''' I named him after his mother.
-->'''Diane:''' I'm a mother? Why didn't you tell me?
-->'''Anthony:''' You said you didn't want to be a part of my life.
-->'''Diane:''' Oh! Anthony, he's the most beautiful thing I've ever seen! He looks just like me!
[[/folder]]

[[folder:Literature]]
* In ''Literature/JohnDevil'' by Creator/PaulFeval Henri tells Temple at one point that [[spoiler: The Killer, John Devil, is actually his half brother, Tom Brown, who he claims is Temple's son by an adulterous affair with Helen Brown. This is most likely all a complete lie however, it doesn't fit the total fact.]]
* {{Averted}} in many, ''many'' ways in ''Literature/LegacyOfTheForce'', ironically with the prospective father being Luke: Luke and Mara think that "Brisha"'s mother is Luke's ex-girlfriend Shira Brie. Mara asks Luke "Who is Brisha's father?" Luke replies "How should I know?", realizes what Mara's asking, and says their relationship was emotional, ([[SeriesContinuityError even if it was based on her lies that almost got him killed]]) and never physical. [[spoiler:Oh, and Brisha '''is''' Shira, a.k.a. Lumiya.]]
* [[Literature/NUMASeries Dirk Pitt]] ended up with twins after it emerged that his girlfriend hadn't actually died. He becomes a good father really quickly.
* In a Franchise/StarTrekExpandedUniverse novel, the character Xyon is introduced at the beginning of the story and helps save the day. At the end, he punches out TheCaptain Mackenzie Calhoun before informing him his full name is Xyon of Calhoun. Nice first impression.
* Creator/WilliamButlerYeats wrote a poem in which Cuchulainn's son leaves home with a vow (apparently designed to give him extra chances to get into fights) not to give his name but at sword-point, that is, after being beaten, and only against someone who's sworn the same. He runs into Cuchulainn in short order, and as Cuchulainn has been under the same oath since childhood they have an epic fight. Cuchulainn gives him a chance to withdraw and live, and says his head looks like 'a woman's head that I loved once.' Then he gets into his berserk mode and mortally wounds him, and demands his name before he dies. And he's Cuchulainn son of Cuchulainn. He is stricken. The people he was partying with earlier predict that once he's done mourning he'll kill everybody to work off his feelings, so they get the druids to enchant him so he gets in a fight with the ocean instead.
** The poem is ''Cuchulainn's Fight with the Sea'', and is extra head-banging in that it was Junior's '''mother''' who told him to make the vow and go to the precise place Cuchulainn was to be found, thereby guaranteeing them a fight in which the father didn't know he was killing his son. Apparently based on an actual myth/saga thing in which this happened to Cuchulainn, only in this one his wife was actively trying to get revenge on him for leaving her through their son.
* Random does this to Arthur Dent in ''Literature/MostlyHarmless''.
* ''Literature/TheDresdenFiles'': Given the spoilers for ''Changes'', [[spoiler: Harry Dresden himself]] is going to get a good dose of this.
* In Brandon Sanderson's ''{{Mistborn}}'', Vin identifies her long-lost father, since her brother had pointed him out to her. The father didn't know she existed until she pointed him out to his boss.
* In [[DependingOnTheWriter some versions]] of the [[KingArthur Arthurian mythology]], [[BigBad Mordred]] is the son of Arthur and [[BrotherSisterIncest his sister]], who was [[MosesInTheBullrushes sent away]] [[ParentalAbandonment to die]] as an infant, as he was destined to kill Arthur later on. Which [[YouCantFightFate he did]] when he showed up as an adult. It can also be a SelfFulfillingProphecy in some stories, as Mordred grows to hate Arthur precisely ''because'' he did this.
* ''Literature/KafkaOnTheShore'', a novel by Creator/HarukiMurakami. The relationship is not spelled out but rather strongly implied, in the manner of: "Are you my mother?", "Why, you have to ask?"
* In Creator/MichaelCrichton's novel ''Literature/{{Next}}'', one random story involves a man working I can't remember where. A young woman with a baby walks up to him and claims to be his daughter. Naturally, he doesn't believe her. She then reveals that she went through a long and arduous process to find out who donated sperm to her mother, despite the fact that it was supposed to be anonymous, spending years just to discover her dad. [[MoodWhiplash And then berates him for donating "defective DNA."]]
* The novel ''Sunrise'' in the Literature/WarriorCats series when [[spoiler:Hollyleaf]] announces not only to her father, [[spoiler:Crowfeather]], but to the whole gathering of cats that [[spoiler:Jayfeather, Lionblaze, and Hollyleaf]] are actually [[spoiler:Leafpool's kits, not Squirrelflight and Brambleclaw's, and he's their father]].
* In ''Literature/TheChroniclesOfAmber'', this happens to Random, as well as to Benedict (who finds he has a great-granddaughter, Dara), and Corwin (who finds he now has a son by Dara).
** To their credit all three men promptly go all PapaBear upon discovering their offspring. As Corwin's sidekick observes "Paternity hits you lot hard."
* Fred Vargas's Commissaire Jean-Baptiste Adamsberg has a one year-old son with Camille, but also a twenty-seven year-old son, Armel, whose existence he ignored until Armel, at the time believed to be the Zerquetscher, told him while threatening him with a gun in ''An Uncertain Place''.
* {{Averted}} in [[Literature/{{Dragonlance}} Dragons of Summer Flame]] by a character raised by a race of island dwelling fae who is mistaken for [[SquishyWizard Raistlin]] [[JerkAss Majere]]'s daughter. She seeks him out, and he promptly tells her she's mistaken.
* In Creator/MichaelFlynn's ''[[Literature/SpiralArm Up Jim River]]'', Donovan is in denial, and the harper doesn't want to talk about once she realizes. When Donovan puts it together, the conversation that ensues has both this, and LukeIAmYourFather.
* ''Literature/{{Dune}}'' had Baron Harkonnen learning [[spoiler:immediately prior to his KarmicDeath]] that the girl who [[spoiler:poisoned him]] was his granddaughter. His reaction in the miniseries makes it pretty clear that he was extremely shocked that she was his relative. Her mom, BTW, was the byproduct of a rape from him by one of the witches.
** Considering the Baron's preferred sexual partners were young men, the Bene Gesserit witch [[StalkerWithATestTube had to use some coercion to make him rape her]], as part of the Bene Gesserits' long-term breeding plans. The Dune series is very weird sometimes.
* In Literature/TheFireUsTrilogy, one of the characters reveals to the audience and his father to be one of the President's sons, presumed dead for years. Interestingly enough, he may or may not have known it himself for most of the series. Our protagonists are [[DysfunctionJunction damaged goods]].
* In ''Literature/RedeemingLove'', BrokenBird Angel gets revenge on the father who [[ParentalAbandonment abandoned her]] and allowed her to be [[RapeAsBackstory sold into prostitution]] by [[spoiler:sleeping with him]] and then revealing that she is the daughter he hasn’t seen in eight years. This is [[spoiler:a major factor in his subsequent suicide]].
* In PoulAnderson's "Literature/TimeLag", realizing that Elva feels a FishOutOfTemporalWater, her rescuers quickly tell her that her son did indeed survive, and that one rescuer is her grandson -- he quickly takes her hands -- and she, indeed, has an infant great-grandson.
* The rare gender inversion is found in TheLostStars series, precipitated by a Sci-fi technology: When the ever suspicious Morgan finally get's evidence that her co-adviser Malin has been acting behind their leader's, Arthur Drakon's, back by falsifying his official DNA records, Malin explains to Drakon one-on-one that this was done by his "mother" to hide his real parentage: [[spoiler:Morgan. His mother was a doctor examining Morgan before she left on a suicide expedition into alien space using cryogenic technology to survive the time it would take to arrive. She discovered Morgan was pregnant, and being barren herself, secretly acted as a surrogate for the child, who was Malin. Morgan was eventually recovered but left otherwise unaware of her child, who tracked her down out a sense of duty, only to find she was psychotic and then stuck around to protect her and protect everyone from her. Drakon is thrown through a loop by the revelation, especially because Malin is the polar opposite the gung-ho, emotionally manipulative Morgan and a biological year older than her due to the cryogenic shenanigans. They both agree that Morgan can't know, as the shock of it would likely drive her to kill Malin out right, given their otherwise already near murderous rivalry.]]
[[/folder]]

[[folder:Live-Action TV]]
* ''Series/BuffyTheVampireSlayer'': Twilight does this to Buffy and Angel.
* [[spoiler: Alex]] in ''Series/{{Lost}}''. Oh, come on, we all knew the moment the name came up.
** And of course there's Daniel Faraday, telling [[spoiler: Eloise]] "I'm your son" right after [[spoiler: she had shot and killed him]]
* ''Series/MacGyver''
* In ''Franchise/StarTrek,'' both Kirk and Picard had plots where they discovered their sons. Picard's son wasn't, Kirk's was (and Kirk knew about him, but the audience sure didn't).
** Worf also got two (sort of), the first in which he had no idea his one night stand with the half-Klingon ambassador had any results and then she showed up with their son, and the second in [=DS9=] when said son shows up to serve the Klingon Defense Forces on Worf's ship with no warning.
** In [=DS9=], a subversion occurs. Garak can only get Tain to drop the superior officer/inferior officer and mentor/protégé "formalities" of their relationship and behave as a genuine father and son when Tain is on his deathbed and even then Garak has to fight Tain into submission over it. The subversion comes from the fact that Tain and Garak have known the true situation between them for Garak's entire life, but there was no public acknowledgement of it because Tain feared having a biological son was a weakness someone in his [[TheSpymaster position]] couldn't afford. He uses his dying breath to admit he was proud of Garak which is all Garak really [[WellDoneSonGuy wanted to know]].
* Subversion, maybe: In a ''Series/{{Supernatural}}'' episode, Dean goes to revisit the site of a 9-years-ago one-night stand and discovers that the woman has an 8-year-old son with remarkably Dean-like mannerisms. She swears the kid isn't his, and claims that DNA evidence proves it, although it is not actually presented to him. The creator later confirmed that the kid wasn't Dean's son.
** A variation in Season 4, where a guy a few years younger than Sam and Dean shows up claiming to be John Winchester's son. [[spoiler: He actually was John's son, but it doesn't matter, since he was dead the whole episode anyway.]]
*** [[spoiler:Angels]] sure fixed that. [[WorldHalfEmpty Don't look like that]]. [[spoiler:The guy got resurrected only to either force Dean into saying yes to Michael or to do it himself. He shows up as Michael's meat suit in the last episode. He, Michael, Lucifer and Sam fall into the pit. Sam's body gets out, but his soul is stuck behind with the rest of them, and when Dean asks ''Death'' to retrieve the brothers, he's given a choice of saving Adam or Sam's soul. Since Dean doesn't really have any leverage to begin with, he picks Sam.]]
** [[RuleOfThree And then again in Season 7]] in which it's played straight. [[spoiler: Dean fathers an Amazon, who is BrainwashedAndCrazy and sent to kill him in order to fulfill a coming-of-age ritual. At the end of the episode they get into a stand-off and Sam kills her to protect Dean.]]
* ''Series/RedDwarf'' did a weird variant on this where Lister ended up fathering a kid...who later turned out to be himself through AppliedPhlebotinum time travel. (Don't ask. It's ''Red Dwarf''. [[MST3KMantra What do you want, logic?]])
** This is likely based on Creator/RobertAHeinlein's famous StableTimeLoop story ''Literature/AllYouZombies'', about a time traveling [[spoiler:hermaphrodite]] who ends up being [[spoiler: his own father, mother, child, lover and the guy who convinced him to take up time travel in the first place.]] Time travel can be like that.
** There's another example of Luke, You Are My Father in the Literature/RedDwarf novel ''Last Human'', with the character Michael [=McGruder=].
* Series/LawAndOrderCriminalIntent: Bobby Goren has just discovered he has a nephew (son of his junkie brother Frank.) Bobby wants to parent the kid but the kid is currently missing and on the run from the cops. Bobby's family is [[DysfunctionJunction messed up.]]
** Bobby also learns that the man he *thought* was his father wasn't - his real father was a notorious serial rapist and killer.
* On ''GilmoreGirls'', there is a situation which could be (but isn't) the source of this trope name. A girl shows up in Luke's diner saying she is doing a science fair project in genetics to find out who her father is by testing the three guys her mother dated around the time she was conceived. It turns out Luke is her father. This is used to derail the upcoming wedding. Lorelai's father semi-lampshades this when discussing insurance with them and warning about tricksters and grifters, saying "It's just that the ''timing'' is a little suspicious..."
* Daniel Meade of ''UglyBetty'' recently discovered that he had a son.
** [[spoiler: Except that it was recently revealed that the father is really Daniel's brother Alex (who is now Daniel's sister Alexis).]]
*** And then by the end of series, both were [[spoiler:PutonaBus and never heard from again]].
* ''{{Beverly Hills 90210}}'': Gina was introduced in the later seasons as Donna's wrong-side-of-the-tracks cousin related through her mother's sister. With the help of some nifty software that included every single birth certificate ever made, Donna discovered [[spoiler: Gina and Donna share the same father, making them half-sisters raised in separate homes]].
* EarthFinalConflict: Liam "Kincaid" is the ChildByRape of Agents Sandoval and Beckett by Ha'Gel. He knows this, but his mother was mind-wiped to prevent her from exposing the Resistance. Beckett only finds out when she's dying from a [=CVI=] breakdown. It's a good question as to whether or not Sandoval figured it out.
* On ''Literature/TheVampireDiaries'' Elena discovers [[spoiler: Uncle John is her father]] and uses this knowledge in a confrontation to force him to let her go.
* ''Series/HomeAndAway'' added an extra twist: John Palmer has a daughter named Shandi, but the Shandi he met was an impostor. Eventually, the real Shandi had to show up.
* At the end of the second series of ''Series/{{Merlin}}'', Merlin meets his long-lost father, Balinor, for the first time. Balinor had no idea he had a son.
** Morgana says this sort of thing to Uther at the end of the third season, though he already knew. It was a Luke, You Are My Brother for Arthur, though.
* In the French series ''Les Bleus, Premiers Pas dans la Police'', rookie detective Laura Maurier is the daughter that police chief Santamaria never knew he had, and she eventually tells him so.
* In the revival of ''Series/DoctorWho'', in the sixth series episode "A Good Man Goes To War," [[spoiler:River Song tells Amy and Rory that she is their daughter Melody Pond. She tells them this after her newborn self is kidnapped.]]
** There's also Rose going back to when she was a baby and saving her father. She has to [[IncestIsRelative fend off some flirting from him right at the start]], but he eventually figures it out more or less on his own. Later, after overhearing that the nineteen-year-old Rose is Pete's daughter but missing the "from the future" part, her mother is understandably {{squick}}ed by the appearance that her husband a) fathered a child when he was about twelve and b) gave her the same name as the baby they currently have together.
** Then Rose crosses over into a parallel universe where Pete's alive but never fathered a child with Jackie, and we go through it all ''again'', this time with Pete having to come to terms with the fact that he has a daughter in a parallel universe with the same name as his ''dog''.
* In one episode of ''Series/TheFreshPrinceOfBelAir'', a young man appears at the Banks' doorstep and introduces himself as Geoffrey's son. Apparently Geoffrey's ex-wife had given birth to him after their divorce and didn't bother to inform Geoffrey.
* In an episode of ''Series/TheRopers'', a 30 year old man tells Stanley that he is his son.
* The protagonist of ''Series/LifeUnexpected'' is a 16 year old girl that was never succesfuly adopted that seeks emancipation and reunites her birth parents who a judge makes them their legal wards after deeming she is unfit to be emancipated, her father thought she had been aborted and when he was told in the first episode he had a daughter it was an instance of this, the girl's father is just a friend of the girl's mother as she has a fiance of her own.
* ''Series/{{CSI Miami}}'', Horatio and his son.
* ''Series/{{CSINY}}'', meanwhile, has a variation with Mac finding out he has a stepson. His late wife gave birth as a teenager and gave the boy up for adoption. He came looking for her later, and though Mac had to tell him she had died, he still eventually formed a friendship with the kid.
* In the mini-series ''Series/TheTenthKingdom'', a [[GenderFlip gender-flipped]] version occurs. [[spoiler: Virginia has to tell the Evil Queen that she is her daughter. The Queen has no memory of her daughter but slowly begins to remember bits and pieces of the past. Including that she [[OffingTheOffspring once tried to drown Virginia in a bathtub]] before she found the portal to the Nine Kingdoms.]]
* What kicks off ''Series/OnceUponATime'' is that Emma makes a wish to stop being alone. Seconds after she blows out her candle, she gets a knock on the door and one trouble-making little boy going "Hi Mom!"
* In Series 4 Episode 5 of ''Series/{{Misfits}}'', Finn tracks down several men with whom his mother Mary was intimate around the time of his conception to determine which of them is his biological father. To Finn's embarrassment, most of the men rule themselves out by claiming to have only engaged in sexual activity with Mary that was unlikely to result in a child.
* In a rare female version, Series/AllyMcBeal opens her door once to find a young girl there who said that Ally was her mother. Seems Ally had donated an egg once and the girl is her biological daughter.
* In ''Series/GeneralHospital'', after seeing Bobby bond with her baby son Michael, Carly blurts out that they're mother and daughter. Considering Carly had single-handedly ruined Bobby's life--such as stealing her husband and suing her for custody of Lucus on the anniversary of BJ's death just to name a few things--Bobby is ''less'' than pleased with this news.
* In ''Series/SleepyHollow'' it is revealed that [[spoiler: Henry Parrish]] is actually [[spoiler: Ichabod and Katrina's son Jeremy, who was thought dead. He's also the Horseman of War, having been driven crazy spending 200 years [[AndIMustScream buried alive]] and then resurrected by Moloch. He is hell-bent on getting revenge on his parents for abandoning him, although Ichabod at least can't be blamed for that since he died before Jeremy's birth.]]
* In ''Series/Believe'', the audience learns [[spoiler: Tate is Bo's father]] at the end of the very first episode-''they'' don't until the seventh, however.
[[/folder]]

[[folder:Music]]
* JohnnyCash's ''Boy Named Sue'' pulls this on his father, who he is hunting down to kill him for, well, naming him Sue.
[[/folder]]

[[folder:Mythology]]
* Cuchulain and Connla, in the Ulster cycle of [[IrishMythology Irish myth]].
* Similar is the story of Sohrab and Rustum. Rustum, the Persian Hercules, has fathered a son but received the news that it was a daughter (so that he would not drag the son off on dangerous adventures). As a young man, Sohrab goes off looking for his father, and ends up fighting against him in a champion-versus-champion confrontation between two warring armies. Sohrab gives out that he is looking for Rustum, but Rustum conceals his identity as he feels it beneath him to be acknowledged fighting a lesser man one-on-one; and also because he thinks Sohrab is only glory-seeking, and will make peace and go away boasting of having met Rustum as an equal. Only after Sohrab is fatally wounded does he learn Rustum's identity and offer his father proof of his ancestry, eventually convincing him. Written up by Victorian poet Matthew Arnold based on the Persian original, see http://www.victorianweb.org/authors/arnold/pva356.html.
* OlderThanFeudalism: In GreekMythology, Theseus pulls one on Aegeus when the former enters Athens as a badass victorious hero. [[Theatre/{{Medea}} Aegeus's wife]] is not very pleased.
* Various interpretations of ''Literature/{{Beowulf}}'' hint at Grendel being Hroðgar's son and also though never outright stated in the text... Beowulf is the Dragon's father. Explicitly interpreted in the [[Film/{{Beowulf}} 2007 animated film]]. [[spoiler: Grendel's mother is [[{{Squick}} the seductress]]]].
* In various medieval legends, Helena was separated from her husband and [[TextileWorkIsFeminine supports herself and her son]] until young Constantine's grace and charm draw his father's attention, leading to revelation that he is his son, and a parental reconciliation.
[[/folder]]

[[folder:Tabletop Games]]
* In ''Franchise/BattleTech'', Kitsune Kurita, son of Omiko Kurita and grandson of Coordinator Theodore Kurita, publicly revealed to Victor Davion that Victor is his father due to a [[StarCrossedLovers clandestine affair]], which his conception from was concealed from Victor. By that time, Davion/Kurita relations fostered by mutual enmity with the Clans had degraded, and the propaganda on both sides exploded over the revelation. A conspiracy to mount a coup against the current Coordinator using Kitsune as the replacement was quashed since their "heir" was revealed to be "poisoned" by Davion blood, and the Davions portrayed Omiko as a salacious Kurita harlot that tried to corrupt Victor. Vic was just happy that there was some legacy of his love for Omi, who was claimed by assassins from Victor's sister, [[GodSaveUsFromTheQueen Katherine]].
[[/folder]]

[[folder:Video Games]]
* Slightly subverted in VisualNovel ''{{Ever 17}}'', [[spoiler: as the character in question already knew. It didn't stop her from fiercely denying it when her estranged children confronted her, or being a bitch to them before they worked it out. Played straight with the other character, who reacts typically for someone his age to the news.]]
* Throughout ''JadeEmpire'', it's slowly revealed that Dawn Star is Master Li's daughter. When you confront him with this, his response is approximately, "So what?"
* In ''LostOdyssey'', the pair of {{Tagalong Kid}}s that Kaim and company befriend bring the party home to meet their ill mother... who immediately recognizes [[spoiler:Kaim as her long-lost father]], making the kids [[spoiler:his grandchildren]].
* In ''{{Sacred}} 2'', the class-quest of the Inquisitor involves you running into your long-lost daughter, with a number of interesting consequences. Firstly, being a man of the cloth, you're not supposed to have children at all, and so you must keep the matter quiet and kill anyone stupid enough to try and blackmail you about it. And secondly, you have to PetTheDog and keep your daughter out of the trouble she constantly finds herself in. Funnily enough, when she finally finds out that you're her father, she's... less than pleased.
* ''Franchise/FireEmblem'':
** If you didn't kill [[spoiler: him]] when [[spoiler: he]] was your enemy early in the story, [[spoiler: Mareeta]] from ''[[VideoGame/FireEmblemJugdral Thracia 776]]'' recruits [[spoiler: her until-then DisappearedDad Galzus]] by telling him this.
-->""When I was [[spoiler: under the control of that evil blade]]...I met [[spoiler: my father]] in a dream. I was still little when I was separated from [[spoiler: my father]], but I still remember [[spoiler: him]]. [[spoiler: He]] was strong, kind, and gentle... [[spoiler: Galzus]]... You're my [[spoiler: father]]!"
** A ''lot'' of cases in ''VideoGame/FireEmblemAwakening'' via [[KidFromTheFuture time travel]]. The first is [[spoiler: "Marth", actually Chrom's daughter Lucina, who had been born earlier in the year it was revealed.]] Later on, the parents pretty much take it in stride.
* At the end of ''MetalGearSolid4'', [[spoiler:Jack aka Raiden]] gets his happy ending when he learns that [[spoiler:Rose didn't suffer a miscarriage, and that Rose and Campbell's marriage was a sham to protect his son from the Patriots. Even better, his son John isn't afraid of Jack's cyborg body and thinks that his father is awesome.]]
* In ''VideoGame/DragonAgeII'', Hawke's uncle Gamlen can learn that he has a daughter at the end of the quest "Gamlen's Greatest Treasure".
* Roger Jr., Roger's son [[KidFromTheFuture from the future]] in ''SpaceQuest IV''.
* The ending of ''StubbsTheZombie'' reveals that [[spoiler:Stubbs and BigBad Andrew Monday arefather and son respectively, with Maggie Monday having slept with the then living Edward Stubbleton before he was gunned down by her father (this also explains why Stubbs is so madly in love with her).]] Needless to say, the son is disgusted to learn this.
* Spoofed in ''VideoGame/{{Portal 2}}'' with the insane ramblings of the Space Sphere, who insists that Space is his father and "now [they] are a family again".
** He's also in a mod for ''Videogame/TheElderScrollsVSkyrim'', where he can claim that his father is dragons. [[AllOfThem All the dragons.]]
* In ''VisualNovel/SteinsGate'', Suzuha is looking for her father in 2010. [[spoiler:Mayuri figures out it's Daru.]]
* The ending of ''VideoGame/BioshockInfinite'' reveals that [[spoiler:Elizabeth is actually Booker's daughter Anna that he once sold to Comstock as an infant to deal with gambling debts. His attempts to save her at the last moment is why she lost her pinky finger, having lost it due to a PortalCut as the Tear between Booker and Comstock's worlds closed.]]
* Invoked by a minor character in [[BaldursGate2 Baldur's Gate 2]]. The player character overhears a conversation between a cleric and a woman claiming that the child accompanying her is theirs. She's halfway through demanding money to help raise the child when said child says they "[[IdiotBall like]] ''"[[IdiotBall this]]'' "[[IdiotBall daddy"]], revealing her trick. She later tries the same thing on the player.
[[/folder]]

[[folder:Webcomics]]
* ''Webcomic/TheOrderOfTheStick'': Elan's father may have spoofed LukeIAmYourFather when he showed up in [[http://www.giantitp.com/comics/oots0723.html this strip]], although it's a case of LukeYouAreMyFather because Elan's father was introduced one strip before the reveal except for a flashback [[http://www.giantitp.com/comics/oots0050.html here]], in which he wasn't named. Still, the "reveal" came as no surprise to someone with a good memory.
* ''TheInexplicableAdventuresOfBob:'' Jean is a bit [[InsistentTerminology insistent]] that all of the peanut butter monsters generated by her project are, in a sense, her children. Nonetheless, she seems freaked out every time she encounters one for the first time.
* In ''Webcomic/{{Niels}} & Gang'', a young teenager shows up and claims to be Niels's child by a Danish woman he had an affair with as a teenager. Duncan is automatically suspicious of Niels Jr - with reason, as it turns out his name isn't Niels and he isn't [[spoiler: exactly]] Niels's son. [[spoiler: He's transgender and was born female; the name he was given at birth is never revealed, but Niels gives him a new name, Magnus, to avoid confusion.]]
* ''Webcomic/LastRes0rt'': Veled tells White Noise that she is his daughter. At first, he [[http://www.lastres0rt.com/2014/07/shes-serving-tea-secret-bonus-comic/ doesn't believe it]]. A few pages later, [[http://www.lastres0rt.com/2014/07/believe-it-or-not-what-else-is-there-secret-bonus-comic he's properly convinced]].
* In ''Webcomic/{{MYth}}: Distillation'' there's a variation. Zeus, being the dense dork he is, needed for Metis to reveal that the girl in his dreams is the result of their "embrace" on that night in Gaia's garden. Zeus, of course, freaked out.
-->'''Zeus:''' You...You mean she's my...?! \\
'''Athena:''' It's rude to point.
[[/folder]]

[[folder:Web Original]]
* In Runescape Gods Exposed, Iban shows up in one episode saying Zamorak is his father. Judging by his response this has been going on for a looooong time.
[[/folder]]

[[folder:Western Animation]]
* ''WesternAnimation/{{Gargoyles}}'' - when Goliath and crew arrive in Avalon, he discovers that the eggs that they managed to save from the clan massacre were brought there, hatched, and were all full-grown gargoyles; one of whom is his (and Demona's) daughter, Angela. The comic later points out that Gabriel, Angela's friend on Avalon, is the son of the two Gargoyles that became Coldstone and Coldfire.
** Although this leads to awkward situations for Goliath and Angela. Gargoyles raise their children in a community with no child being the son or daughter of one specific parent. Angela, being raised primarily by humans, [[ValuesDissonance worries a lot about her parentage]] in comparison.
* ''WesternAnimation/BatmanBeyond'': [[spoiler: Due to some... complicated DNA matters, Bruce Wayne is the biological father of both Terry '''and''' Matt [=McGinnis=].]] And [[spoiler: it wasn't Bruce's fault; Amanda Waller arranged it to ensure there would always be a Batman.]]
* LukeIAmYourFather is parodied in WesternAnimation/{{Futurama}} ''Benders Game'' with [[spoiler:Igner revealing to the professor he's his son]], complete with ripped lines from StarWars and a lightsaber duel. This was made especially funny by the fact that they were '''supposed''' to be ripping off the Fantasy genre, but still managed to slip into sci-fi.
* ''WesternAnimation/TheSimpsons'' had an episode in which Mr. Burns's long-lost son turns up - voiced by (and drawn to look like) Rodney Dangerfield.
** Later on, Krusty's long-lost daughter shows up.
* Dermot from ''WesternAnimation/TheVentureBrothers''. [[spoiler: DoubleSubversion: He believes himself to be the long lost son of Brock Samson. Turns out... he's actually ''Rusty's'' kid.]]
* In ''WesternAnimation/YoungJustice'', the exchange is completely non-verbal and takes about ten seconds. And it's a whammy, with Superboy revealing to Superman that he is his clone.
** Happens again in season 2 at the end of "Salvage" when Jade shows Roy their baby girl Lian.
** Happens yet again in "Bloodlines" when Bart announces that He's Barry and Iris's grandson from the future.
* The main reason that Eva from ''WesternAnimation/ObanStarRacers'' chases after Don Wei is because of this trope, although when she meets him, he doesn't recognise her and she [[LineOfSightName takes up the name Molly]] instead. [[spoiler: He works it out eventually.]]
* In the season 4 finale of ''WesternAnimation/{{Archer}}'', Lana reveals that she conceived her daughter [[spoiler:using a frozen sperm sample Archer donated after a cancer scare a couple seasons ago. Archer doesn't hear the explanation due to his tinnitus acting up, but he figures out the truth when his newborn daughter uses his trademark "shut up while I drink" finger gesture while nursing. As he "meeps" in shock, Lana introduces him to his daughter Abijean.]]
[[/folder]]

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