Think about it this way. If there was a neighbor who came into your home, bullied your son, made fun of him, stole his food, and manhandled him would you think that he ought to have a relationship with her? Or would you say "I don't ever want to see you in my house again! Get out before I call the cops!"

So why would you think that he ought to have a relationship with this woman just because she shares some DNA with him?