The Decedent's Estate Account uses the PC583 Form (PDF). Note: Please type or print neatly in black or blue ink.Directions for Completing Account Form in a Decedent Estate. PC 584 – Long Form. A small estate affidavit can offer a streamlined and costeffective way to settle a deceased person's estate in Michigan without probate. Learn what happens in a probate estate in Michigan after a person's death. From the Probate and Estate Planning Section of the State Bar of Michigan. To close a bank account on behalf of someone who has passed away, you must have legal authority to manage the account. Your nephew would simply file an affidavit of decedent's successor with the credit union, in order to obtain the the account. The personal representative is also required to file a final account with the court at the conclusion of administration of the estate.