I have a brother in law who is in his early 30's and hes a pharmacist and he behaves like a child. He keeps calling me names like idiot and stupid and calls my sister who is his wife worse names. And treats her really bad and is just an overall miserable person. It would be easy for me to take physical action here and give him reasons to think twice before he calls one of us an idiot or stupid again but my sister would be upset if I did that. I want to resolve this in a nonphysical way. Whats the best course of action here and should I let him know things may become physical if he doesn't stop?