can my father in law move money from his account to his sons

my mother in law left my father in law after 61 years of an abusive marriage, She is getting assistance so the told her she had to take her name off of their joint bank account so she did. they said to keep her name on the deed to the house. my father in law went to the bank the same day my mother in law went to a divorce lawyer and took all the money out and out it in my brother in laws account. Can he do that?