I've dealt with some "families" like that. Worthless wastes of oxygen is the kindest way I can describe such people.
These types tend to be rather nuts plus have issues like drug addiction (primarily pills and meth) and shady means of income (theft, scamming, begging, selling pills, etc)...they get kicked out of section 8 housing and fleabag motels and then they hit the road.
The ones I dealt with didn't start a fight but I was always prepared for the possibility...glad I never had to fight a brawl with a bunch of them.