My mom received a class action settlement after she died. Is stepfather entitled to that money?

Stepfather created an estate after moms passing and told her children the settlement would be in trust account for them. He actually took the money and kept it in his personal savings. He did go to a lawyer who sent letters to all 7 of her children requiring signatures to waive right to probate. Unknowing to her children what he was doing, they signed. The children believe the settlement would have been for her next of kin which makes them believe what he did was wrong if not illegal. The letters the children received stated that the lawyer represented our father, which he is not. I would like to understand my rights as her biological child.