In this Love Triangle, two of the participants are parent and child. Common flavors are the mother who steals all her daughter's boyfriends, the father and son competing for the same woman, and the fantasy of a mother and daughter threesome. Family ties can cause dramatic tension if the love triangle is the parent and child as romantic rivals, and it can have an Incest Is Relative flavor if the triangle involves a threesome, either invoked or onscreen.
- Wicked (1998) (the movie starring Julia Styles, NOT the Broadway play) revolves around a budding young girl who murders her mother for cheating with the neighbor and starts seducing her father. She is slowly gaining control over everything when he falls in love with a lifelong friend. Things come to a head the night after the father remarries.
- The episode "Jackpot" has a gay one of these, though a one sided one. Both the killer and his dad were in love with the victim, and the son killed the victim because he was jealous of the father having a relationship while the victim wasn't in love with him.
- There was another ep with a mother-daughter one; the daughter killed the mother because she was in love with the stepfather.
- In an episode of Family Guy Lois, feeling old and unattractive, seduces Meg's boyfriend.
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