Parents having favorites

Could you post anonymous?

My parents favor my daughter over my son. My daughter is 6 and my son is 3. My parents never let him come over but always want to keep my daughter. They say he’s too rambunctious and would get hurt. Recently, I confronted them. They said that my son needed to stop hitting his sister. ( they fight about toys, play wrestle, etc.) they’re both guilty of it and are always disciplined for it. My mother says my son has anger issues. My father sent me some messages saying that he would make sure a stop would come for my son specifically hitting his sister. When I confronted him on this he added he would send someone to my house once a week to check on her. What am I suppose to do in this situation? I feel as though despite all they do for me and my daughter, them leaving out my son makes them very toxic and I should distance ourselves.