Baby is orphaned. Loving parents find baby. Parents raise baby as their own. This is a standard set-up in stories. But sometimes, as the baby grows up, they find out that they're a little... different from the rest of their family. Really different. Sometimes they notice this, and start angsting.
And sometimes, they don't notice anything at all and are perfectly content with living their lives with their families, no matter how obvious it is that said family isn't their "real" family. This is taken to extreme measures in Funny Animal cartoons, where the species is very different but the adoptee doesn't notice.
Usually played for laughs rather than straight these days, due to the dying out of the Changeling myth and parents these days avoiding keeping adoption a secret from their kids. For the "humans raised by animals" version, see Raised by Wolves. See also No Social Skills, the inevitable behavioral problems that come with such an adoption, and Happily Adopted, which is what they tend to be. Compare/contrast Chocolate Baby, which generally involves something other than adoption. Compare Red-Headed Stepchild.
- A commercial for Newcastle Brown Ale has a light-skinned blond learning "[he] wasn't born a Kapur."
Friend 1: I'm sorry, Sanjay.
Friend 2: ... Is that why your curry is so bad?
- Played straight in season 5, Digimon Savers, in which a boy, Ikuto, is raised by Digimon. He completely fails to notice a lack of evolving, the whole "gradual growth" thing he has going, the lack of special abilities, the fact that his name doesn't end in "-mon", and the fact that he bleeds. Also, somehow, he talks like Tarzan despite most Digimon being quite well-spoken. The fact that he was raised by a living female snowman from quite an early age and really should have frozen to death upon being rocked to sleep one too many times is never even addressed.
- In Digimon Adventure, Koushirou, AKA Izzy, was this before the series started, and his parents (actually, his biological parents' cousins) intended to keep him this way until he'd grown up enough to handle the truth. Unfortunately, Koushirou overheard them talking about it one night, which caused him a lot of angst until they were able to sort things out. Trying to keep a secret from any series's Smart Guy doesn't usually work.
- Subverted in Rumiko Takahashi's Fire Tripper: a flashback shows that the female lead Suzuko realized on her own that she was adopted (as her parents had no baby photos of her) and, when Mom and Dad came to her with the intention to tell her, she told them that she already knew, and thanked them for raising her lovingly. She's actually a little girl from Medieval Japan who was thrown in time and space, alongside a boy from the modern era who was tossed into Feudal Japan and grew into the male lead Shukumaru. They stay in Medieval Japan and get married there.
- In the manga Hikkatsu! Strike a Blow to Vivify, Momoko was raised by pigeons, a fact she casually mentions (to justify her knowledge of pigeon-style kung fu) but never explains despite repeated requests by other characters.
- In Macross Frontier: Ranka is at first unaware that she's the adopted younger sister of Ozma Lee. When she eventually does find out, there's minimal denial or angst over it, as Ozma has always loved her as though she were his sister. The reasons why she was adopted, on the other hand...
- In Project ARMS, Ryo, Hayato, and Takeshi were all taken in at birth by agents of the Blue Men organization. Ryo and Hayato don't realize this until the Egrigori come after them. Takeshi accidentally finds out sooner and goes on an angst-trip until he gets over it and saves his sister from danger. All of them pretty much continue to accept their parents as their own.
- In Rave Master Yuma reveals at the end of the Blue Guardian arc that the baby Hardner's wife was expecting when she died survived the crash that killed their mother. Yuma has been raising Nagisa ever since. He forbids anyone from mentioning this again, particularly to the adopted child.
- Lain doesn't look much like her family in Serial Experiments Lain. This is because she's adopted. Lain's an Artificial Human whose "family" is an experiment. They were made to take care of. This explains why they're so distant, and sometimes distasteful, towards her.
- In Hungry Heart: Wild Striker, protagonist Kyosuke Kanou was this during his early childhood, as his biological parents died in a car crash when he was a baby. His discovery of this, coupled with the fact that people constantly put him in the shadow of his Big Brother Mentor Seisuke, led him to become heavily estranged from his family, and to quit soccer altogether. He eventually gets better.
- Yu-Gi-Oh! ARC-V: It turns out that the Yuya and Yuzu were adopted by their respective parents they were living with and they had no real birth parents to begin with. The two and their respective counterparts are composites of Zarc and Ray, a result of the Original Dimension being divided by four. This would also explain why Yugo and Rin are orphans.
- Played rather straight in the French comic book Les 5 Mondes de Sylfeline. The human heroine, Sylfeline, is reared by Douniais (basically pudgy gnomes) and believes to be one of them until told the truth on her sixteenth birthday... despite being twice as tall as her adoptive parents (and five-fingered unlike the four-fingered Douniais).
- Subverted in the French manga-style comic book Appa. The title heroine is called by her father on his deathbed, who starts saying that he has an important reveal to make to her. When she realizes he's about to tell her that she is a foundling, she points out that she noticed they were different a long time ago. (She's a little human girl; her adoptive parents are anthropomorphic walrus.) The father is quite upset by this fact, ranting that he wouldn't have agonized for so long over not telling her sooner if he'd known, while the mother rolls her eyes.
- Similarly spoofed in a strip by French comic book artist Claire Bretécher. A couple tries to explain to their (young adult) children that they were adopted, being apologetic that they've waited so long to tell them. The parents are White; the son is Asian and the daughter is Black, yet both were oblivious. When finally clued in that they're Not Blood Siblings, however, they immediately and happily Get a Room!
- The French comics Les Psys ("The Shrinks") has a couple bring in their kid for help because though they never told him he's adopted, he got that yelled at him by other kids on the playground and he's been asking himself if he is. Since the parents would rather wait until he's older to tell him, the shrink goes into the consult room and asks the kid why he thinks he's adopted (kid's Black, parents are White).
- In John Byrne's retelling of Superman's origin, Martha Kent, who had suffered two miscarriages and a stillbirth, was horrified that anyone would shoot off a rocket with a little baby in it. She claimed to have given birth to Clark, and she and Jonathan preserved the secret throughout his childhood — which, naturally, meant keeping it from Clark. Only when Clark's powers started to emerge did Jonathan confess. In this version of the retelling, they were able to get away with it due to Smallville suffering a blizzard soon after they found Clark that kept them inside for weeks, and due to her previous miscarriages the neighbors bought that she wouldn't have shared news of her latest pregnancy until the kid was actually born.
- Happens in W.I.T.C.H., where, during the New Power story arc, Taranee finds out she's been adopted, as her parents had to give her up when she was a baby when magic summoned a meteor from the sky to burn evil vines trying to kill her, burning up the home in the process. Her adoptive parents had planned to tell her later and kept track of where her birth parents are so she could meet them, but she made clear she considers them her real parents.
- The Dog from Footrot Flats was raised in a cats' home, by a cat-obsessed old lady, and for many years thought he himself was a cat. He got over it. Similarly, Horse originally thought he was a baby coat.
- One series of comics involved Garfield being stuck up a tree and encountering a cat who was adopted by squirrels.
- A week of strips in 1982 involved a baby chick thinking Garfield was its "mommy" (and later "daddy" when it was corrected). The last strip has Garfield finally getting the chick to go away. The chick forlornly says "Goodbye, daddy." In the last panel, Garfield sheds a tear.
- One gag in the German comic Nicht Lustig has a penguin mother tell her adopted giraffe son the harsh, yet so very obvious, truth. In the background, a naked human man can be seen thinking, "Wow, poor guy."
- "The Ugly Duckling" is really a swan adopted by ducks. Though cygnets do resemble ducklings, but with a dull pearly gray color.
- In The Elements of Friendship, Butter-and-Eggs is an Earth Pony raised by a Stag named Cobnut, who comes complete with a set of sticks he wears as antlers. Turns out he put them on himself at a young age and forgot they were fake. He gets over being told pretty quickly.
- In Empath: The Luckiest Smurf, Empath among the Psyches during his early years, before he found out that he was really a Smurf. He and the other Psyches were led to believing that he was merely a "prototype Psyche".
- Gensokyo 20XX:
- Later on in the series, we seem to have this with Marisa, who, according to Ren, doesn't seem to know or care that she was adopted by two kitsune.
- In Foundling (branch off), Reimu doesn't seem to notice or think much about being taken in by youkai. However, she was too young to understand otherwise.
- In Neither a Bird nor a Plane, it's Deku!, Izuku is completely unaware of the fact that he's adopted until his Kryptonian abilities manifest at the age of four. More specifically, his Super-Hearing lets him overhear the police talking about how different his abilities are from his parents and that medically speaking, he shouldn't have powers. This allows him to put two-and-two together and confronts his parents about it, who are forced to tell him soon afterward, though he ends up hating what he hears.
- In the Fairy Tail fanfic Obsessed Lucy and Natsu plan to advert this with a baby girl they've adopted. Said girl was stolen before she was even born by a psychopathic woman who used a spell to impregnate herself with her and killed the real mother and suspected of killing the woman's boyfriend as well. Months after being caught the woman gave birth to the child. Due to the status the child would end up having in the public eye, they had Mest take the child in secret. Luckily, Lucy had been pregnant during the same time period and gave birth on the same day. During a solar eclipse no less. They are able to play it up to the rest of the world that Lucy had twins. Most of the guild, for the time being, believes this as well. However, they make it clear that they will tell her, and the rest of their kids, the truth and why they are keeping it a secret as they grow up.
- A particularly bizarre example of this occurs in Pokemon: Shadow of Time; after Sabrina is purged of the psychic parasite that controlled her since she was 12, although she's physically in her mid-twenties she's mentally regressed back to the girl she was when she was originally possessed, with the result that she has somehow 'imprinted' on Ash and Misty as her 'parents' even though they're only in their teens, continuing to consider Ash her father even after she's mentally 'aged up' back to adulthood.
- Not Completely, Altogether Here: Rora never knew she was adopted. Her mother is a short Munchkinlander while she's Gilikin tall (as in, her mother barely reaches her elbow), but it was thought just to be genetics. Turns out that she's the heir to the Ozian throne, the next Ozma.
- In the French movie Les As de la jungle: Opération banquise (The Jungle Bunch: The Movie), the hero Maurice is an antarctic penguin that was adopted by a tiger from the day he hatched. He later himself adopt a tiger-striped fish as his son. Unlike other examples of this trope, Maurice never ever clues in that he's not a fierce tiger, even after meeting some other penguins (whom he considers "silly-looking birds"). He goes as far as regularly painting yellow stripes on his black plumage to keep the tiger look.
- Eggs from The Boxtrolls is convinced he's one of the eponymous boxtrolls until Winnie convinces him otherwise. It just never seemed to occur to him that there was a reason he looked nothing like his adoptive father or the rest of the family for that matter. He just figured he was "long-boned," and had some sort of skin condition and a "speech impediment".
- Disney's Hercules has this trope in full force, with the accidentally-exiled baby god being taken in by childless mortals, only to grow up feeling weird and ostracized because of his excessive strength.
- Thank goodness for Ice Age 2: The Meltdown. The directors had a grand old time with their subplot about a woolly mammoth who had been raised by opossums — and who played dead and clambered up trees. Somehow. She spends most of the movie trying to sort out her species identity crisis with fellow mammoth Manny's help. The situation is awkward because Manny had, up 'til then, believed he was the Last of His Kind, and his motives for helping the only female mammoth he knows come to terms with her species aren't exactly altruistic. Made still more awkward when one re-watches the original Ice Age film and realizes that Manny is so conflicted about the whole thing because his wife and son were murdered quite recently. It does explain his extreme over-protectiveness in Ice Age 3: Dawn of the Dinosaurs, though. Speaking of the third movie, this trope gets played surprisingly straight with Sid and the baby dinos, since he's the first thing they see when they're hatched.
- Kung Fu Panda:
- Hilariously dealt with, and lampshaded. Quite obviously, there is no way Po the panda could be the biological son of Mr. Ping the goose, but the issue is never addressed. However, just after the valley is evacuated, and Mr. Ping again impresses on Po that he is meant to be a noodle-maker, this exchange occurs:
Po: I don't know, Dad. Honestly, sometimes I can't believe I'm actually your son.
Mr. Ping: Po, I think it's time I told you something I should have told you a long time ago...
[a long pause]
Mr. Ping: The secret ingredient in my Secret Ingredient Soup!
- Dealt with in the sequel. It turns out that no-one bothered to talk about it despite it being so obvious because Mr. Ping is afraid of Po leaving him to find his true parents. Ultimately, Mr. Ping should have had more faith in his adopted son's love.
Po: I just found out that my dad isn't really my dad.
Tigress: ...your dad?
Tigress: The goose.
Po: [nods again]
Tigress: [no change of tone or expression whatsoever] ...That must have been quite a shock.
- Inverted in the third film; Po meets his father who was revealed at the end of the second movie and doesn't recognize him. At all. Even after said father says the only reason he's in town was that he was looking for his son. Rather than state the obvious, Po instead wishes him good luck and the two part ways. Everyone else involved facepalms. When the Furious Five meet Li-Shen, they immediately guess that he's Po's father.
- Hilariously dealt with, and lampshaded. Quite obviously, there is no way Po the panda could be the biological son of Mr. Ping the goose, but the issue is never addressed. However, just after the valley is evacuated, and Mr. Ping again impresses on Po that he is meant to be a noodle-maker, this exchange occurs:
- Lambert the Sheepish Lion: Only Lambert himself is out of the loop; all of the other sheep know and (aside from his loving mother) mock him for not acting like his actual species, though eventually Lambert does discover his inner bestial nature when a wolf imperils his mother.
- Greenie from Leafie, a Hen into the Wild is a duck while his mother is a chicken. He doesn't realize that he's adopted until his preteens when he's teased by other ducklings.
- In Disney's Tarzan, Tarzan believes himself to be an oddly hairless and skinny gorilla, until Jane and the other humans show up. In the original book, he comes across the jungle hut his shipwrecked parents built for themselves before dying, and from the picture books inside figures out that he's not an ape. He also teaches himself to read.
Tarzan: Why didn't you tell me there were others like me?
- Inverted in Changeling, where it's the mother who finds out the child is different. In this case, though, the mother knew immediately the kid wasn't hers. And it's revealed pretty much everyone else, including the boy, involved knew as well, the corrupt police department just wanted to say that the case of the boy's disappearance had been solved.
- Barry in The Country Bears was raised by humans since he was a cub, though his human brother seems to be the only one that finds having a bear in the family ridiculous. Also invoked by this exchange:
- Dumb and Dumber To: When Harry learns that he needs a new kidney, he visits his parents (who live just down the street) to ask them for one. He is astounded that his Asian-American mother and father aren't his blood relatives.
- Inverted in Easy A; the son is fully aware that he is adopted, while the father is (jokingly) shocked when he nonchalantly mentions it and demands to know who told him.
- Elf: "Of course you're not an elf, Buddy. You're six-foot-three and had a beard since you were fifteen."
- In The Jerk (1979), the title character (who is white) is raised the son of poor black sharecroppers. When his adoptive parents reveal "You're not our natural-born child," he responds with "I'm not? You mean I'm gonna STAY this color?" Later in the film, the character is shown to STILL consider himself black. When one of his business advisers uses a racial slur in passing while discussing keeping "niggers" away from the business, he responds "You, sir, happen to be talking to a NIGGER!" He then proceeds to kick the guy's ass with some previously unseen martial arts expertise.
- Reversed in Murder by Death. It apparently took Lionel Twain more than a decade to realize that his adopted son Sydney Wang was Asian.
- Inverted in The Omen: Damian seems to implicitly understand his true heritage from when he is very young. He also has agents to guide him to his destiny and he accepts their roles without reservation.
- Splitting Heirs plays this for laughs with its protagonist Tommy Patel, who was adopted by an Indian family living in London as an infant and grows up to be blond, blue-eyed Eric Idle; he's stunned when his family breaks the news to him.
Tommy: Y-you mean I'm not really Asian?
- The film version of Stuart Little plays it kinda straight in the start, but the cute little mouse gets over it quite quickly. His human brother, on the other hand...
- It's sort of noticeable in Thor that Loki doesn't quite look like his parents or his brother, and doesn't question it even though it's assumed that he's lived for over a thousand years. And even when he discovers his true heritage, he kills his true father and tries to annihilate his own race.
- The reveal of an older, non-adopted sister that looks very similar to Loki in Thor: Ragnarok provides a partial explanation about why. Perhaps they inherited their looks from a grandparent?
- In a particularly heartwarming example, in the film, Losing Isaiah the African-American child is adopted by a white family from birth and doesn't seem to suspect anything. So when his white older sister tries to call attention to it when he is 4 years old, she asks him "Isaiah look at our hands, what is different about them?" He responds, "My hand's smaller!" and then goes back to playing.
- Disney's The Ugly Dachshund concerns a Great Dane who was adopted into a family of Dachshunds. The Great Dane grows up thinking he is a dachshund. Hilarity Ensues. (This has happened in Real Life.)
- In the incomprehensible Atlanta Nights, Bruce Lucent doesn't notice he's black and both of his "parents" are white until adulthood. As with most of the book's plotlines, this lasts for exactly one chapter and is never spoken of again.
- A Brother's Price: This is invoked with Neddie at the end of the novel. She is actually the child of a family executed for treason, and a toddler at the time she is adopted. The Whistlers do everything to help her fit in, from dyeing her hair to giving her the same tattoos her "sisters" have. They seem to hope that she will forget about her birth family, and not want revenge once they tell her the truth when she comes of age. Wanting to keep the adoption under wraps is justified by the cultural norms of the setting — the major religion frowns on adoption. The main character speculates that this is because the skewed birthrate makes boys so much more valuable than girls, and abandonment of excessive female children might be more prevalent if other families could be convinced to take them in. An oblivious adoption is the only option to avoid scorn.
- In The Chronicles of Narnia novel The Horse and His Boy, Shasta, a boy raised in Calormen, learns he was adopted when he eavesdrops on his "father" talking to a nobleman spending the night at their house. The nobleman was quick to realize this because Shasta has the pale skin of the northern nations while Calormenes are noticeably darker. As his "father" is willing to sell Shasta to the nobleman, he chooses to run away and find his real family and turns out to be the long-lost prince of Archenland.
- Captain Carrot fails to realize he's not actually a dwarf, despite being over six feet tall (his dwarf name means "headbanger"). In later books, he says that being a dwarf is more about culture and mindset than actually, you know, being a dwarf. He isn't wrong, either. On the Discworld, being a dwarf is a great deal more than mere species. Most dwarfs accept (if not always happily) that Carrot is a very, very, very tall dwarf. There are also people who are biologically dwarfs but have done away with the cultural trappings, and probably wouldn't be considered dwarfs even by Carrot — people such as Count Casanunda or Hwel.
- Going Postal features the eccentric young postal assistant Stanley Howler, who was raised by peas. Not on peas. By peas. The mechanics are left to the reader's imagination.
- I Shall Wear Midnight reveals, not too surprisingly, that Wee Mad Arthur is a Nac Mac Feegle raised by gnomes.
- In Snuff, children's book author Miss Beedle relates how her mother was raised by goblins and was quite happy being one until some humans decided to "rescue" her from the only family she'd ever known.
- The Doctor Who Eighth Doctor Adventures have a strange inversion. The Eighth Doctor adopts a young girl named Miranda who nonetheless has a very Strong Family Resemblance to him, except for the fact she's blonde. They're even the same height once she's fully grown. And apparently neither ever wonders whether they're blood relatives. People who've met both of them tend to be surprised to find out that she's adopted. Miranda's birth father turns out to be the last survivor of a war that ravaged Gallifrey. Given that children of the Doctor have a tendency to look like the Doctor's previous regenerations, there's a fairly good chance that Miranda and the Doctor are biologically related.
If he hadn't known she was adopted, he'd never have guessed. She looked just like her stepfather.
- Dragaera series by Steven Brust:
- The Dragaeran Morrolan never questions why he's about a foot and a half taller than his adoptive human village, nor why he's still young at more than 100 years of age. It takes another Dragaeran to seek him out and explain things.
- In a less conspicuous example, Zerika IV was raised by Dragonlords, and eventually deduced that she was an orphan of that House whom they'd adopted. It's only when Sethra Lavode summons her for training that she learns she's the last Phoenix, which explains her blonde hair and un-Dragonish personality traits.
- In a Dragonlance short story, an ogre loses his memory in the Cataclysm... and is adopted by a clan of Gully Dwarves. An adult 9-foot-tall ogre adopted by a bunch of creatures under 4 feet that can't count to 3. Hilarity Ensues. Later he gets his memory back and gets angry... but simply can't bring himself to hurt the little creatures that treated him like family.
- Played with in The Face On The Milk Carton. Janie has no doubts about her parentage until she sees a child that looks startlingly similar to her kid self on a milk carton, labeled as a missing person. When she goes to see the missing girl's family, she notices that they all have red hair similar to hers. This revelation strikes her adoptive parents, too, who had raised her believing that she was their grandchild.
- In Funhouse by Diane Hoh, the narrative shifts from third-person to first-person accounts from the villain, who is recalling how he found a diary hidden in his family's attic, revealing that he was adopted, or rather, sold, after his birth parents were financially ruined by an unscrupulous group of businessmen who wanted control of the boardwalk containing the titular funhouse. The diary belonged to the villain's mother, who felt she had no choice but to give her son up because she didn't have the strength to raise him. The villain goes on a Roaring Rampage of Revenge aimed at the teenage children of the owners of the boardwalk, killing one and crippling two in roller coaster accident. It turns out the villain is in fact the main character's brother.
- From The Halfblood Chronicles, Lashana was raised by shapeshifting dragons and was convinced that she was one who had somehow got stuck in human form — her adoptive dragon brother thought so too! It helps that neither knew that humans and elves existed except as forms for dragons to shift into, being raised in the middle of a desert.
- In Murderess, Déaspor reveals to Hallwad and Aucasis that they are actually Killers. Of course, being Déaspor, she does this incredibly insensitively.
- Sarah McGregor of Lurlene McDaniel's One Last Wish book series. Her parents spent her life convincing her she was a "Miracle Baby" that took forever for them to conceive, only for her to find out the truth when she needs a bone marrow transplant and her siblings volunteer theirs. She tries to reconcile with her birth mother only to learn An Aesop about how her "real family" is the one who raised her.
- Warrior Cats:
- Fireheart's sister Princess gave her firstborn kit to ThunderClan because she wanted to choose the destiny of one of her children. Cloudkit was too young to remember what happened. He didn't learn that Brindleface was his adopted mother until Fireheart told him when he was nearly six moons old.
- Bluestar, then Bluefur, had her kits raised in RiverClan by Graypool. Stonefur and Mistyfoot didn't learn their heritage until adulthood. It probably helped that their adoptive and biological mothers looked rather like each other and that the whole litter looked almost exactly like their mother.
- In The Wheel of Time series, Rand al'Thor is eighteen years old before he discovers that farmers Tam and Kari al'Thor are not his birth parents. This revelation doesn't change the fact that Rand still loves them just the same and resolutely refers to them as his real parents, even after uncovering the identities of his royal biological parents.
- In Andre Norton's The Zero Stone, Jern first learns he was adopted when his father was dead. His mother uses it to justify her Parental Favoritism. It enrages him to hear he is not his father's son, but later he consoles himself with the knowledge that his father preferred him because he was in mind more like him than the blood children.
- One episode of 30 Rock had the characters' mothers appearing on the show. Danny (who is white) reveals he has an Asian mother, which someone comments on and thus him realizing he was adopted.
- In Arrested Development, Lindsey Bluth was adopted, and her parents claimed she was Michael's twin sister... in spite of her being three years older than him. When Lindsey obviously started going through puberty before Michael, Lucille hand waved Lindey's growth away by simply claiming she was getting fat.
- Made-for-TV Movie Based on an Untrue Story features Morgan Fairchild, who never questions the fact that her parents are Asian and she's a tall blonde up until the minute the plot requires it.
- An odd case was referenced in one episode of Cheers. To account for Coach's absence towards the end of season 3 (his actor had died before the end of the season, he would be explained away as being somewhere. One of these cases was being at a family reunion- and everybody aside from him in the photo is African-American. Turns out, he was mailed an invite to one of their gatherings by accident and felt it would be rude not to go. Hence, he showed up at more of their family functions and was considering holding the reunion at his house that year (the family called him "Uncle Whitey").
- In the Season 3 finale, Phoebe Buffay learns her mother, who committed suicide when she was a teenager, was actually her adoptive mother and the old friend she just managed to track down is her birth mother.
- In season 10, Monica and Chandler want to adopt a baby since the odds of them getting pregnant were minuscule. Phoebe sets them up with a couple who have adopted. During the visit, Chandler accidentally tells the boy that he's adopted, something he hadn't known.
- Doctor Who: "Night Terrors" inverts it in a frightening way. The Doctor visits a little boy that's scared of everything with a mysterious cupboard giving him off-the-scale readings on his sonic screwdriver. When asked about his birth, the father reveals his wife can't have kids. The Doctor reveals the kid is an alien and is using a perception filter to make it seem like they always had him. This is how his species normally reproduces. They find a childless couple and leave them with one of their young. They're pretty much alien cuckoos.
- In Game of Thrones Jon Snow hasn't the slightest clue of being adopted by his biological uncle Ned Stark, whom he believes to be his biological father. His biological parents are actually the deceased Rhaegar Targaryen and Lyanna Stark, who have been dead for all of his life. As Lyanna knew she was dying, she manages to pass her infant son (Jon) into the care of her brother, Ned, and asks him to protect her son from Robert Baratheon before she dies. Ned brings Jon home with him, raises and loves Jon as his own son alongside his other children, and spends the rest of his life protecting his sister's son by hiding Jon's biological parentage by claiming Jon as his own illegitimate son since the current-reigning regime, the Baratheons, would kill Jon if they ever found out he was the hidden son of Rhaegar Targaryen and Lyanna Stark.
- Justified on The George Lopez Show — George's family is Hispanic, but since his sister's adoptive parents are Italian the racial issue wasn't glaring enough to clue her into the truth. Apparently, she had to "correct" people who thought she was Latina fairly often before finding out it was true, though.
- In the Made-for-TV Movie Knight Rider 2010 Jake, the lead character, was adopted at a very young age by a black man. As an adult, the man tells Jake he's not his real father. "I know... I have no sense of rhythm."
- In NCIS, Abby discovered she had a biological brother named Kyle whom she never met after undergoing a blood test in order to donate a kidney. She later compared her own DNA to that of a strand of her mother's hair she kept in a locket and discovered that the two samples didn't match.
Abby: I can't imagine the wonderful loving parents that raised me and Luca ever giving up a child. But they would have adopted a child. And they did... me. I'm adopted, Gibbs.
- In one episode of NewsRadio, Matthew doesn't figure out that he's adopted until his "identical twin" brother points it out to him. This despite the fact that the two look absolutely nothing alike; Matthew is played by gangly, blond Andy Dick, while his twin brother is played by Jon Stewart. Turns out at the end of the episode that Matthew knew he and his brother weren't really twins but kept pretending he did so that his brother wouldn't catch that HE was the adopted one (an unseen photo of their parents confirms Matthew is their biological child by nature of a startling resemblance). One wonders why their parents didn't tell them they were fraternal twins. There's also a line suggesting they're not the same age, making it unclear why they were called twins at all. Then again, Matthew's parents could be as strange as he is.
- Invoked and averted in season 8 of Ru Pauls Drag Race. Naomi mentions that she's adopted, and another contestant asks her if her parents ever had to have an awkward heart-to-heart with her. Naomi says that since she's black and her parents are white (and her twelve siblings are similarly a mix of ethnicities), that was never really necessary. Also a case of Happily Adopted - Naomi openly gushes about how much she loves her Massive Numbered Siblings and especially her mom.
- One episode of the Israeli sitcom Shemesh shows Sasis parents, who turn out to be very wealthy, educated, and look nothing like him. He discusses with fellow Ditz 'Ogen the possibility that he might be adopted, and when he finally goes to ask his mother, it turns out they've actually told him that he is, several times, only he never bothered to listen. (Of course, that's just one explanation of Sasis origins.)
- In Upper Middle Bogan, Margaret kept Bess's adoption from her for over thirty years, and there's no suggestion she would have told her if she hadn't suddenly found out their blood types were incompatible.
- Wizards of Waverly Place: plays with this. First, we meet a kid who claims to be the runt of his giant family when he was about the same size as a normal human. Then later it turns out he's adopted. Which he knew, but he'd always assumed he'd been adopted from other giants Despite the fact he was a wizard.
- Greg's father from Yes, Dear spent much of his life without knowing he was adopted.
- In the video game FTL you can find an alien Mantis that was raised by humans and believes it is a human. Treating it like one and talking to it with a human crew member is one of the ways to get a positive outcome to the event.
- The Flut Flut in Jak and Daxter: The Precursor Legacy very briefly adopts Daxter as its mother, despite being approximately 50 times the little orange rodent's size (they milk one joke out of this, and then it turns into a steed — but never again chirps "Mama" in Daxter's direction).
- In the The Legend of Spyro series, the title dragon was adopted by dragonflies. While they do tell him that he's not their biological son, they reassure him that they will always be his "real" family nonetheless. The Oblivious comes from the fact he never figured out he wasn't a dragonfly despite the fact he's many times their size, can't fly (yet), and has legs. He'd never seen a dragon before in his entire life and the dragonflies hadn't either, so there's no way he could've known what he really was, but those should have at least been a clue.
- The Legend of Zelda: Ocarina of Time. Hey, Link, guess what? You're not a Kokiri! Seen to a lesser extent in Twilight Princess, where Link is an orphan living among the Ordon villagers. His long ears give away his Hylian descent (despite Shad insisting he's not from "Hyrule proper"), but the rest of the villagers have human ear-shapes, which might imply they come from a different ethnic/racial background in Hyrule. Given how popular and well-liked he is, though, it's clearly a superficial issue at most.
- In Princess Maker, some of the daughters know that they're adopted, but some don't. Those who don't are Patricia from the fourth game and Musume from the fifth one.
- SongBird Symphony: Birb at the very beginning of the game. The realisation that Uncle Pea is probably not his biological family is what prompts him to go looking for answers about his origins.
- In Super Mario RPG: Legend of the Seven Stars, Mallow is first encountered as an oblivious adoptee (he is a Cloudy/Marshmallow being and his family are frogs). His reason for joining the party thus ends up being to search for his birth family. The game does play his obliviousness (and most of the other tadpole's) for laughs.
- Star Ocean: The Second Story is kinda silly about this, as her pointed ears make it kinda obvious Rena is not only adopted but a different species from the rest of her village. The Town Elder doesn't want to bring it up. The third game justified this in the in-game encyclopedia; because expellians are a hybrid race, they have a much wider variety of physical features than other humans. So while Rena's ears were a bit unusual even by their standards, they didn't actually stand out that much. Also, Rena isn't oblivious to adoption. Everyone only thinks she is. She was, but overheard her adoptive mother and the town elder talking about it after her adoptive dad died. (Mom wants to tell Rena she's adopted, the elder somehow talks her out of it.) By the time the game begins, she's known for a few years. Though she doesn't find out she's a different species until Disc 2.
- Parodied in a storyline in Sluggy Freelance. Torg snaps under the stress of his life and becomes "Torgo of the Jungle" (again), and is adopted by a family of centipedes infesting his filing room.
Narrator: Living in peace behind pieces of furniture, scurrying under old paperwork, Torgo deals with the fact that somehow, he is different.
Torg: Pa? Why don't I have poison glands and two pairs of maxillae?
Pa: 'Cause you're a freak. Now put Comedy Central on, it's time for The Daily Show.
- Ozy from Ozy and Millie, a fox, knows he's adopted but still sees the Llewellyns (dragons) as his "real" family. However, he does seem to have odd ideas about what normal family activities actually are, given his loopy relatives. And the Llewellyn family curse seems to regard him as one of the family; in fact, he's the only family member it has any noticeable effect on since he's the only "dragon" with fur. Ozy did meet the person who was quite probably his biological father once. Upon learning this, Ozy decided to spend the day with the father who raised him, rather than the father he had never met before (and as far as we know, never saw again).
- Love Me Nice: Carolina was somewhat taken aback to discover that she was a toon. At first, it's not established whether they deliberately didn't tell her because they thought the inevitable conversation would be awkward, or if they assumed she'd take a look in a mirror now and again and figure it out. A later flashback shows Carolina's mother dodging the question of why she had weird ears, and apparently allowing her to believe she was deformed, which strongly suggests the former.
- Diane in El Goonish Shive didn't realize she and her sister were adopted despite them being different races. Justified in that she was only six at the time so was too young to understand ethnicity and presumably just assumed that sisters generally had different skin colors. Word of God said he originally was going to have Diane always know about her adoption but realized he was looking at it from an informed adult perspective.
- The Bird Feeder:
- Inverted with Darryl and Edna, two cardinals, and their adopted children, who, in the very first strip are revealed to be an adopted bluejay and titmouse, and were only adopted because Edna is colorblind.
- Done more traditionally with Tina, a hummingbird. In #163, "Bunnies," she tries to find her real parents, as she herself was raised by rabbits, and accidentally adopts a rabbit.
- The eighth ASDF Movie has a bit where an owner surprises his dog by telling it it's adopted.
- In a Jacksfilms YIAY video, Jack tries different ways to tell his dogs that they're adopted.
- SuperMarioLogan: In "Rosalina's Parents!", we find out that Rosalina was Happily Adopted by two Space Aliens; she doesn't believe what Mario says about the two not being her real parents until the Aliens tell her themselves.
- A cut scene from the Adventure Time episode "The Lich" was going to reveal that Finn didn't realize he was adopted, despite being raised by talking dogs. It was presumably cut for being a blatant continuity error: Finn had shown he specifically knew he was human (it makes him soul-searchy) and "Memories of Boom-Boom Mountain" shows that he apparently remembers his adoptive parents finding him in the woods.
- Done in The Angry Beavers with the (mostly) inanimate character Stump, in the episode "Stump Looks for His Roots". After showing off slides of his family, Norbert points out that Stump must be adopted (or a "transplant", as he puts it), since Stump is an elm, and his parents are oaks.
- Growing Up Creepie: It's rather obvious that Creepie knows that she's adopted, since her parents are bugs, although she never talks about it since she's happy with them.
- Technobear from Harvey Beaks was raised by turtles, and he thought he was one as well until the end of "Terrybear".
- Rocko's Modern Life has Heffer being surprised he's adopted after Rocko brings it up at a dinner visit to his family. Rocko, at least, found it obvious, as Heffer is a steer and his family are wolves. Who originally raised Heffer so that they could eat him, incidentally. They came to love him and changed their plans, of course. Heffer didn't take it well at first, but he eventually settled into Happily Adopted.
- Ike on South Park is an interesting example: while Ike himself is just a baby, his older brother Kyle was apparently unaware that Ike was really adopted from Canada, though Canadians on South Park are animated differently than Americans. Subverted somewhat in that the viewer couldn't be sure of this, either; this episode is basically what established that rule, though Canadians had been shown animated differently before (on a Show Within a Show, which could have been another explanation for the style difference).
- On SpongeBob SquarePants, Mr. Krabs, a crab, is the proud father of Pearl, a whale. The show treats this as an Elephant in the Living Room/Unusually Uninteresting Sight.
- An episode of Tom and Jerry had a duckling imprint on Tom and remain oblivious to Tom's attempts to eat him (despite Jerry repeatedly saving him and trying to illustrate the difference between cats and ducks). When the duckling finally figures things out, he decides to let Tom eat him anyway, though of course Tom can't bring himself to do it and, at the end of the episode, actually takes the duckling in.
- The trope is pushed to an extreme level of silliness in the Animated Adaptation of Trolls de Troy. The heroine, Waha, is a human girl who was adopted by a family of trolls (in this world, big, hairy, smelly, man-eating humanoids). She stays utterly oblivious to this fact (unlike in the original comic, where her adoptive father reveals the truth to her in the first issue, when they desperately need her to use magic). In fact, she responds with violence to the mere suggestion that she could be human. Instead, she thinks of herself as a troll with a "thwarted pilosity" — and the other trolls believe it too! Of course, trolls are notoriously stupid and scatterbrained, but even her adoptive parents seem to have forgotten about the little matter of her adoption. The worst part, however, is that even every human she encounters (admittedly, barely smarter than the trolls in general) also swallows the "hairless troll" story. This includes an experienced troll hunter (who wants to add her head to his trophy wall) and a "trollologist" (but he is crazy anyway). Chances of Waha ever realizing her true heritage? Zero.
- Ugly Americans: Lionel, Leonard's apprentice, "son" and heir to the title of Wizard of Social Services (also a Harry Potter Expy, second in the series), was abandoned at a Chinese restaurant. He speaks English with a British accent, despite being raised by Chinese immigrants. He's also 50 years old despite being a child, physically.
- In The Jungle Bunch, Maurice is a penguin who was raised by a tiger, and now thinks he is one. The same applies to his adopted son, who's a fish.
- In the Foghorn Leghorn short "Mother Was a Rooster", Barnyard Dawg, as a joke, hides an egg under Foghorn, making him think he'd laid the egg, even though he is male. It turns out to be an ostrich egg, but Foghorn still thinks he gave birth to the ostrich, without question.
- Bloom of Winx Club was sent to Earth and adopted by Mike and Vanessa when her home planet was under attack; in the process of such, she lost her memory and thought they were her parents. After having a dream of the time she was rescued and Mike reveals it's her, she learns the shocking truth.
- Cuckoos. This picture◊ shows just how obvious it should be to the chick's new parents. Of course, if the parents catch on and shove the cuckoo chick out of the nest, they get their nest destroyed and their feathery asses kicked by the adult cuckoos of the neighborhood as a warning not to do it again — the "cuckoo mafia" theory.
- Truth in Television for people. Feral children who are raised by animals take up the habits and behaviors of the animals they're raised by, including that animal's attitude towards humans, be it fear or indifference.
- A woman wrote into an advice column, telling about the time when she commented on an Asian baby's adoption by white parents and the parents blew up that she had "given it away."
- Also Truth in Television with animals.
- Dogs have been known to protect fawns, and in one case an orphaned squirrel was adopted by a mother dog and raised among her litter.
- Most dogs will adopt a kitten into their homes quite easily, which can often lead to odd behavior later in the cat's life.
- In one case in South Carolina, a lost dog who didn't even appear to have a litter was rescued as she was nursing a month-old kitten.
- Some domestic cats have adopted baby squirrels and possibly even guinea pigs.
- To say nothing of the tortoise and the baby hippo it adopted.
- Similarly, a lioness adopted a baby antelope. She became (in)famous for this, as she would kill the antelope's mother in order to facilitate the adoption.
- One informative children's book says that cats before a certain age will not kill things like squirrels. The picture accompanying that statement was so saccharine as to give one diabetes.
- There's even one story from a couple of years back of a lioness rescuing an African girl from a group of men who were trying to force her into marriage with one of them since her cries sounded like those of a lion cub. They found her later being cared for by lions.
- This picture of a cat raised among dogs.
- There's an equally Tastes Like Diabetes video on YouTube of a cat adopting a baby rabbit.
- A farm cat in Ireland adopted some baby ducks that happened to have hatched simultaneously with her birthing kittens in the same barn. The ducklings snuggled with the real kittens for warmth were groomed by the mama cat and even learned to suckle milk from her.
- Although not precisely adoption, there was a case when a human toddler fell into an animal enclosure at a zoo and was picked up and carried to the exit by a female gorilla.
- There's imprinting, most easily observed in chickens and waterfowl. The article mentions a group of goslings believing that a pair of wading boots was their mother. This is why, when zoos raise baby birds to be released into the wild, zookeepers have to feed them using hand puppets to familiarise them with their own species and keep them from becoming too dependent on humans.
- This Cracked article, Tastes Like Diabetes abound.
- Society finches have been domesticated for centuries and breed very well in captivity, while many other finches will abandon eggs easily in captivity. It's very common to have society finches raise eggs for other types of finch.
- Rosie, a kitten raised among huskies to the point she even pants like a dog.
- The orangutan Chantek, who was raised at the University of Tennessee at Chattanooga by anthropologists seeking to test the limits of apes' intelligence and their ability to master human skills. To this end, he was taught sign language, lived at the university campus, and frequently ate human food. After an incident where the now-adolescent (and quite sizable) Chantek escaped his enclosure and startled a female student, he was removed from the university and placed in a research centre, before eventually being moved on to the Zoo Atlanta. When he encountered other orangutans for the first time in his life and a caretaker asked him what they were, he signed, "orange dogs", and did not seem to associate them with himself.