I'm currently stumped trying to remember the word for when someone does something or says something in a consistent manner as part of their personality. For example, my friend Sam always shrugs his shoulders high and smiles when my coworkers ask him redundant questions. I wanna say that's his personality quip or gesture but I know that's not the right word. I feel like it starts with a P but I could be wrong.
I like this one best
: a person's particular way of talking or moving
But some other possibilities include
The word that I would use is
mannerism - something that a person does repeatedly with their face, hands, or voice, and that they may not realize they are doing.
If it is particularly unusual, you could call it a quirk or foible