A bad one obviously.
I disagree
In terms of behavior, a child that's abused by their parents would probably be more cautious or afraid of getting too close to other people.
Children who don't have a certain parent (mother or father, doesn't matter) won't have that influence they should have. So, for instance, if a great father was married to a horrible mother, but the father passed away when the child was young, I'd think the kid would be more influenced by the way the mother acts
I've been without a dad for years now, and he was always very much into sports, short hair, and the whole jock style. Since I've only been raised by my mother, I'm more into everything my dad isn't. Maybe if he were around, I'd be more active or into sports. You never know, though.