What should I do?

My bf has a 2 year old son. He doesn’t live with him. He’s 21 and I’m 19. I want to be with him but my mom doesn’t approve. He has a VERY bad temper and we’ve gotten MAJOR fights. My mom doesn’t approve of him and his son. She doesn’t want me to date someone with baggage and such a bad temper. Should I side with her or stay with him?