How much trauma is “required” for regression? (I’m aware that this is probably a dumb way of thinking about it)

I’m using an abandoned alt account because I don’t want to involve this with my main.

I was just wondering what “level” of trauma usually triggers regression? I’m asking because I think I might involuntarily regress, but I don’t want to claim that if I my trauma isn’t “serious” enough or something. Like, could physical and emotional abuse during childhood trigger any sort of regression or is it usually more serious things?