There is a lot to unpack in your question. Did your father have a will? Did you (or anyone) report your brother's theft while your father was alive? If your father had a will, you need to bring it to the attention of the probate court where he died. If he did not have a will, you will likely need to handle his estate through a process known as administration. Because you mention undue influence and breach of fiduciary duty, I assume your father had a will in place. But I could be in error. In any case, please contact an estate planning attorney as soon as possible to prevent further waste of your father's estate assets.
Answered on Aug 29th, 2016 at 6:18 PM