My sister & brother "stole" money. Using her Durable POA, sister withdrew $10K (full balance) and closed an account that I was sole beneficiary of) all while under the "watchful eye" of WFB. I have hard copy verification of this and other "transactions" my sister and brother have made while handling mom's estate. Can I sue my sister & brother? And how likely would it be that I could include the bank in a lawsuit for errors made on their part?