Does hitting the child while driving count as Child Endangerment/Abuse?

My father and my brother were in the car together talking about his poor grade in school. My father gets furious and starts hitting and yelling at my brother (who is 17) repeatedly while my brother is telling him to calm down and to pull over. While all of this was happening, he had one hand on the steering wheel driving on a busy road at 7AM. My brother resorted to calling our mom who got on the speaker phone and she told my father to calm down and that he should pull over. He ends the call and never stops the car although he did stop hitting him. What can we sue him for? Parental Rights? My brother despises my father personally so I know that he would want that. I would also add that he has been very different ever since that incident. He is very quiet and his eyes seems empty. His friends and teachers also asks him if he’s okay and that he seems very odd.