Everyone laughs it off when Big Bob “hulks out” in the 2002 movie, and when he also fights Nick in Might Pete, but that’s just straight up assault.
Big Bob objectively has it in him to be physically violent. To his daughters and Miriam? Probably not, most likely to those he views as threatening him. But I also wouldn’t test that theory too hard neither.
If the show went on to show Helga’s home life through middle and high school, I think if it were played straight it’d get pretty sad.