Anonymous wrote:You have two things they want (money, grandchild) and they have nothing you want. Why give anything to them?
You could give the money back and never see them again. Or you could keep the money and never see them again.
You are holding all the cards. If you want FIL to stop being abusive, do what you did before. Avoid interaction until they change.
+1. I wouldn't give them a damn thing beyond the middle finger salute and would cut them off immediately.
If you for some reason feel the need to repay them, don't give them more than the current value of the "inheritance"/gift. Absolutely do NOT pay them back more than what you currently have invested. No loans taken out, no borrowing from savings, absolutely nothing additional. Also prepare yourself for the fact (not possibility, fact) that paying them back will stop nothing and solve nothing. They will just abuse you in different ways until you cut them off again.