Should I let this friend go...

Sa

Sooo I’ll probably be eaten alive for this but I want to cut ties with a friend of mine. Our kids are the same age and their best friends but her son is not very well behaved. Our sons are 5 and her son is facing possibly getting expelled from school because of how bad he is. He’s scratched a little girl and made her bleed, punched other kids, spit on a kid last week, and just yesterday grabbed a little girls butt. She vents to me about it and I try to tell her that she needs to get him seen and have a real conversation with him but all she does is beat him but never talks to him really about why he acts that way. I’m really worried about my son picking up her sons behavior because 5 is an age where they want to act like their friends. He’s always a little more mischievous when he’s been around him too long. I don’t know what to do because while I like her as a friend I don’t want our kids to be around each other. I know that sounds awful and I feel bad I do. But I don’t want my son to re-enact those behaviors. We have been friends for 3 years and every year her son gets worse. Again I’m sorry if this comes off harsh. I know he’s a kid but I also want to look out for my sons best interests and keep him around positive kids. Honestly the worst part is that she denies his behavior and blames the school district. She takes no responsibility in his actions. I’ve tried to tell her a million tones that she needs to stop beating him and really sit down and have a conversation with him but she ignores me as if I don’t know what I am talking about. I know it’s not all his fault I really do blame her for the main reason why he acts this way.