My son accidentally transferred money into his soon to be exwife's account instead of mine. We all have the same last name at the same bank, he also sends her money for their child. So he has both accounts in his "contacts". I told her of the problem, she said she would transfer the money back, but the next day she said she was keeping it. The bank told my son nothing could be done but I can take her to small claims. It was a lot of money that she took. What shall I do?
Exactly what the bank said: go to small claims court.
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Divorce / Separation Lawyer
You shall and can do nothing. This is your son's job to do something. He has or should have a lawyer. Perhaps his lawyer can help your son. The bank is not liable to your son's error and you have no authority to do anything.
Real Estate Attorney
And it may be enrichment, but not "unjust". Just because money winds up in what seems like the wrong place doesn't mean she wasn't entitled to it pending the divorce decree's being entered, especially if there are interim orders for child support and maintenance. Which raises a question in my mind: is your son handling his divorce by himself? Because these are things he should be having his divorce attorney deal with, not his dad. You're lucky the soon to be ex even spoke to you.