isn't the only thing that family members can share. Much of the time, family members tend to act similarly, either by having similar habits, taking similar actions when faced with similar decisions, or otherwise having certain quirks indicative of the family. While their overall personalities can be entirely different, individual habits can still be shared between them.
This has the scientific justification of learned behavior in immediate families, since a young, impressionable child is very likely to be watching when a parent or sibing is doing something, so the child will be likely to imitate that behavior.
In several works, this can actually be Foreshadowing
that two characters are related when certain habits are shared between them.
Subtrope to Like Father, Like Son
Anime and Manga
- One Piece: Even before Garp was revealed as Luffy's grandfather, they both showed a Bunny-Ears Lawyer mentality, being more concerned with eating most of the time and often being absent-minded.
- In Naruto the Ninja Families share their powers and inclinations for some reason.
- In the short-lived manga Takama-ga-hara hero Yamato has a Childhood Friend, Mizuho, who's kind of obsessed with being a good match for him by getting stronger. In the penultimate chapter, we see that she has four sisters...who are equally obsessed with Yamato's four brothers, each with the age-appropriate counterpart.
- At the end of Maverick, Annabelle tells how she figured out that Zane Cooper is Maverick's father; that they both draw their guns the same way, kiss the same way, and both sing the same incredible wrong words to "Amazing Grace."
Both Mavericks: Do not!
- In one scene in Back to the Future, Marty facepalms at a diner in disbelief that he's in the past, and the camera pans to his future father, George, who is facepalming the exact same way.
- In The Darjeeling Limited one of the Brothers has a quirky way of planning breakfast by semi-arbitrarily assigning different cereals to each brother. When they encounter their mother, the audience sees that he picked this quirk up from her.
- In the movie What a Girl Wants, Daphne and her absent father Henry put jam on their toast before folding it in half and eating it in the exact same way. They also both have a thing for Coco Pops.
- Forrest Gump: At the end, both young Forrest and older Forrest bend their head in the exactly same way.
- In the Nero Wolfe novella Before I Die, the client, Dazy Perrit, has a daughter, but he has kept her existence and identity a secret to protect her from his enemies. He hires Wolfe to, among other things, break her of a habit she has of shrugging just like her mother did, which he fears has, or will reveal her parentage.
- Jane Austen liked this trope:
- Emma: Mr Woodhouse and his older daughter Isabella, Mrs John Knightley, are both of fragile constitution and very anxious, yet very kind-hearted. They are very particular about their (and everybody else's) health and they couldn't do without their family doctors. They also deeply love their family and they respect their old friends and acquaintances. Oh, and both Mr Woodhouse and Mrs John Knightley are very fond of gruel.
- Pride and Prejudice, both Mr Bennet and his daughter Elizabeth love making fun of silly people. Lydia and to a lesser extent Kitty take after their mother: they are loud, silly and generally embarrassing.
- Sense and Sensibility: Mrs Dashwood and her younger daughter Marianne are both very romantic and have deep feelings (that especially Marianne exaggerates), to the point that it's rather self-harming.
- Fanny Dashwood is envious, greedy and mean. Her mother, Mrs Ferrars, is even more so, yet they are both sure they are perfectly lovely. Quite the evil variant of the trope.
- Mrs Jennings and her daughter Charlotte behaviour would fall into this category as well. They both loved fun, however, it was sometimes very inappropriate.
- Friends did this a few times. As Ross and Monica were siblings they were revealed to have some weird shared obsessions from their childhood, including quiz shows, the Osmonds, a dance routine that they won a school talent show by performing and the "Gellar Family Cup" awarded after family sports matches.
- Similarly when Phoebe meets her long-lost biological mother she discovers that they both use the made up word "floopy". The mother then plays with this by pointing out her love of pizza as another sign that they must be related.
- One Midsomer Murders has Barnaby figure out two women are related when both use the same bizarre expression despite not living near each other, just in time to save the Asshole Victim.
- On Monk, all of Kevin Dorfman's relatives are big talkers.
- In Once Upon a Time, Mary Margaret (Snow White), her daughter Emma, and Emma's son Henry all share a taste for cinnamon sprinkled on top of their hot chocolate. This helps to "prove" that they're all related even though Mary Margaret has no memory of it and Emma doesn't believe it.
- Murdoch Mysteries: A visiting Mountie starts upstaging Detective Murdoch in the areas where he usually excels. They share ideas on how to investigate the case and at one point, they are seen walking side by side, with their hands joined behind their back and deep in thought. It turns out that Murdoch and the Mountie are half-brothers.
- Metal Gear Solid 3 reveals that Naked Snake/Big Boss had an affinity for cardboard boxes like his son/clone Solid Snake. According to the cardboard box trophy for Super Smash Bros. Brawl, Liquid Snake, Big Boss's other clone/son, shares this affinity for cardboard.
- In Pokémon Platinum, your rival (Canon Name: Barry), is always in a rush and is rather impatient. This is shared with his father, Tower Tycoon Palmer, who runs into the player just like his son does.
- The MGS example above is parodied in The Last Days of Foxhound when Liquid is almost convinced by a voice coming from a cardboard board box, but then lampshades how ridiculous it would be to have a cardboard box be a useful disguise. Of course, when Big Boss takes control of Liquid's Body, however, he uses it as he always did, regardless of Liquid's snarkery.
- Ancient Romans were believers in this and it affected elections.