Am I wrong for feeling like this?

Not sure if this is the right place to post but I don’t know where else to put it.

My sister in law and brother in law are very toxic people and are violent towards each other. They have had a ton of issues for the last 9 years and have had multiple incidents with the police and CPS coming to their house. my sister In law is a bad alcoholic too but refuses to get help. Last night at 3 am my brother in law woke up to my sister in law drunk trying to remove their kids from their house. Her brother, sister, and sisters boyfriend were there to help and and her sisters boyfriend ended up beating the crap out of my brother in law. It was so bad the police are charging the guy with attempted murder. But get this, my brother in law plans on staying with her even though she left with their youngest child after my BIL got his head smashed into the concrete. He claims “that’s the love of his life and he would die for her” even though she stood by and watched him get his ass kicked but then left with their child. I’m 9 weeks pregnant and can’t help but think I don’t want my baby around this when they’re born. Am I wrong for telling him that he can’t come around my child if he decides to stay with her? My mother in law thinks that it’s not fair and was upset when I said that but I think it’s justified and he’s just as toxic as her if he stays with her.