A character learns that they're adopted and doesn't take it very well. Maybe they feel they've been lied to or maybe they worry about not being a "real part of the family". Either way, their feelings towards their parents become sour due to the fact they're adopted. The reveal of "I Am Not Your Father" and cries of "You're Not My Father!" are extremely common in these sorts of situations.
Other situations where a character dislikes their adopted parents or hates the fact they're adopted are allowed.
- Mitsumi from Pokémon: Diamond and Pearl Adventure! was raised by the Big Bad Cyrus. She was raised to be a very powerful and violent Pokemon trainer but took a HeelFace Turn prior to the series. She's disowned Team Galactic and considers herself on a Last-Name Basis with her adopted father.
- In Revolutionary Girl Utena, Nanami, who has an incestuous crush on her older brother, is crushed and upset after her brother reveals that both of them are adopted. For some reason, the reveal that they are Not Blood Siblings ruins the magic for her, even though in anime-logic this usually makes their relationship more ok. The Not Blood Siblings aspect is further subverted when it turns out that they were adopted from the same family and are related.
- In Sarazanmai, Kazuki learns as a preteen that he is adopted. This causes him to grow distant from his loving family and brother, particularly after he meets his birth mother, though she seems happy with her new life. This angst is heightened after a confrontation with his brother after the birth mother meeting indirectly leads to the brother being crippled in a car accident, which Kazuki blames himself for and increases his withdrawal from his adopted family.
- In Sket Dance, the "Happy Birthday" arc is a flashback on how the main character Bossun learned he was adopted and the circumstances around his real parents' death. He fled from home in shock, but after a revelation that his parent' death wasn't in vain and confirming his adoptive mother truly loves him, he got over it.
- In New X-Men, Quentin Quire's transformation from a normal student to would-be terrorist is kicked off when he discovers that he's adopted. Already facing ostracism from his classmates because of his serious demeanor, the knowledge that his birth parents apparently didn't want him crystallizes his belief that he is separate from the rest of the world.
- Downplayed in Superman: Secret Origin. Clark is horrified when he learns that he's an alien from another planet and flees into the fields above his parent's wishes. When Jonathan manages to catch up to him, Clark says he just want to be his son. The Kents assure him that he is their son.
- In Neither a Bird nor a Plane, it's Deku!, Izuku doesn't take learning that he's an alien well, as it comes just hours after he nearly killed his best friend with powers he shouldn't have. He declares himself a monster and says that he isn't really the Midoriya's son, since he wouldn't have hurt anyone if that wasn't the case. He becomes a shut-in who refuses to come out of his room whenever possible. Eventually, he gets over his own angst enough to reconcile with Inko and Hisashi and considers them his real parents over his biological parents.
- Anna from When Marnie Was There began living with her foster parents at age 5. She was happy with her life until she recently found records showing that they get paid money for fostering her. This upset Anna and caused her to become very self-conscious and introverted. After she Took a Level in Cheerfulness over the film and learned that her mother wanted to tell her but she didn't know how, and that she loves her money or not, she began referring to her mother as such instead of calling her "auntie".
- In Flirting with Disaster, Mel is so consumed with angst over the fact that he was adopted that it's affecting his ability to care for his own son (he can't even commit to a name for the boy.)
- In Thor, Loki reacts very poorly to learning that he was adopted, both because it focuses all of his buried insecurities about playing second fiddle to Thor and because it also reveals to him that he's been a Frost Giant, one of the Asgardians' ancient enemies, all along. Ironically, his adoptive parents had kept the knowledge from him specifically so he wouldn't feel Adoption Angst!
- The Belgariad: Garion has a bout of this when he learns that the "Aunt Pol" who raised him is actually the legendary 3000-year-old sorceress Polgara, not least because it happens when she downplays their relationship to hide his status as The Chosen One. Zig-zagged later when she clarifies that she's his ancestor's sister and reassures him that she loves him immensely.Garion's orphaning was complete now. He was adrift in the world with no ties of blood or heritage to cling to. Desperately he wanted to go home, back to Faldor's farm, where he could sink himself in unthinking obscurity in a quiet place where there were no sorcerers or strange searches or anything that would even remind him of Aunt Pol and the cruel hoax she had made of his life.
- It's a reoccuring theme in Warrior Cats for characters to stop seeing their adopted parents as their family after learning they're adopted.
- A minor case occurs in the Agatha Christie novel Mrs Mc Gintys Dead, where Maureen Summerhayes says to Robin Upward: "I don't like being adopted, do you?" This statement proves to be crucial in identifying the real killer, as Poirot explains that the "Do you?" part indicated that Mrs Upward was not Robin's real mother, as Maureen would be able to recognise someone as being adopted due to being adopted herself.
- Crank Yankers: In a Season 3 episode, Katie calls up a library to ask the librarian what does the word "mature" and "adapted" mean. Katie states, "My dad said I wasn't mature enough to know that I was adapted". The librarian claims that he must have said adopted, not adapted. Katie then has a breakdown crying and mourning that her parents are black who lied to her that it was just a "weird gene thing" and understandably the librarian frantically works to calm her down.
- The third season of Jane the Virgin reveals that Rafael Solano is adopted, which causes a great personal crisis (since they had a tumultuous relationship with their overbearing father), a financial upheaval, and a thus far unsuccessful search for their birth parents.
- The show Once Upon a Time is kicked off because Henry discovers he was adopted by the Evil Queen, and he is looking for his birth mother. His sense of alienation does wear off over the course of the series, coming to love both of his mothers.
- Parodied on 3rd Rock from the Sun, when Tommy is inventing Earth identities for the aliens:Tommy: Harry, you're adopted, but we haven't told you yet.Harry: Oh... that's gonna hurt.
- Adventure Time: In his backstory, Finn was raised by a family of talking dogs after the parents found him as a baby. Though he loves his adoptive parents, Margaret and Joshua, he also angsts over not knowing where he came from or who his birth parents are, all the more punctuated by the fact that he's never met another human being. When he does eventually meet his biological father, he is disappointed to find that Martin does not actually care about him.
- One episode of Camp Candy has Vanessa receive a letter from her parents. It gets damaged before she can read it and it seems to reveal she was adopted. She spends the rest of the episode angsting over it and even runs away. Nurse Molly doesn't see the problem with being adopted since it means her parents specifically chose her. (But now Iggy angsts over his parents being stuck with him.) After Vanessa sees the light, it turns out she's not adopted, but her family's new puppy was.
- Rocko's Modern Life: When Rocko meets Heffer's family (who are all wolves), he lets it slip that he didn't know that Heffer (a steer) was adopted, causing Heffer to go through this. For bonus points, the Wolf family originally planned to eat Heffer, but ended up falling in love with him.