Not only do you have the opportunity to find out how assets were put to use, but the Personal Representative and the Register of Wills do, too. The Register can look back to the two years preceding death to see if any gifts were made in an attempt to avoid probate (more specifically, inheritance tax).
I would suggest in this case that you speak with an attorney who handles fiduciary matters such as this. Addressing your concerns in a case like this is no small task.
Disclaimer: This answer does not create an attorney-client relationship, it does not constitute legal advice, and it should not be relied upon as such. Laws vary from state to state, and an attorney cannot fully evaluate your situation without a comprehensive consultation and review of all facts and information readily available.
Yes you do and the attorney in fact must produce an accounting for the period of time they had power of attorney. The attorney in fact has a fiduciary relationship and must act in the highest of good faith and not self deal.
Any individual seeking legal advice for their own situation should retain their own legal counsel as this response provides information that is general in nature and not specific to any person's unique situation. Circular 230 Disclaimer - Advice given in this response cannot be used to eliminate penalties with the IRS or any other governmental agency.