I was in a similar situation as yours, OP, many years ago.
At our first house, when my children were very young, there was a home across the street that was Section 8. Over the course of 10 years, we saw many strange things happen there and many dysfunctional families, but while I intensely disliked the parents, I always tried to give the children a chance. If nothing else, I figured the kids could come to my house, be supervised, and perhaps have a healthy meal in a home where no one swore or drank.
I did have rules, and the children that came over knew these rules. There was no hitting, they had to share, no inappropriate touching, no swearing, and respect must be shown to me, and I would be respectful back to them. You know, things you teach your own children but some families don't care to bother with.
One particular family had a little girl that was really sweet, she was the only girl out of 6 kids, all older brothers but for one younger brother. The boys were crazy wild and not welcome, but this little girl and my youngest got along well, so she was over a lot.
One day, her little brother came over. He was 3, and she said that her mom said he had to play with her from now on, so if she came over, he had to come, too. Ok, not sure he will like Barbies, but as long as he respects the rules, no problem.
This boy had no respect for anyone or anything, even at the age of 3. I now dreaded the girl coming over, because her brother was always with her. My daughters were tired of this, to the point that they no longer wanted the girl over. I told them we were the only positive influence these kids had, so we had to try.
I had tried to talk the mom at one time, but she was falling down drunk in the middle of the day and swore at me for stepping on her property. The police were often at the home, at all hours. Gunshots would be heard at times (and then the police again) and in the dead of winter, you would hear the constant swearing even though the homes were all closed up. No way was I able to approach any adult in that home to talk about the children coming to my home!
One day, I had it with the little boy. The kids were climbing the ladder to go down the slide on our swingset, and the 3 year old boy said to my daughter, "get your sex-loving fat donkey out of my way" (ok, with harsher words) and tried to pull her pants off. That was it, I told him that was definitely not allowed, he had had enough warnings, he was to go home and never come back. I told the sister she was welcome to stay, but she said her mom would be mad if she did not stay with her brother. As sad as I was about the girl, I had come to realize nothing I did was going to help this boy learn to respect my rules or me or my children, and I was done. I don't care who you are, you don't swear at my children and insult them just to get your way, then proceed to undress them when you get mad!
I felt bad for the little girl, but I did what was best for my own children. I do believe in looking out for children, and I grew up in a neighborhood where all the parents knew you and you were scared of them, and they all disciplined everyone else's child, but loved them all, too. I tried to be that kind of parent, but was unsuccessful. However, I tried. As bad as I felt to banish these kids from my home, I would have felt worse for never trying.
This family moved out in the middle of the night a few weeks later. They left two Dobermans tied to the back tree.

We neighbors were glad to be rid of them.