Any powers given by the POA ended immediately upon the death of the person that gave the POA. That means if the daughter was distributing assets based on the POA then she had no authority to do so.
The laws regarding who is an heir under the intestate laws are very complicated. Rather than copying and pasting the information I am going to give you a link to a web page that explains who is an heir:
However, a probate should have been done because the property belongs to the estate of the deceased and did so from the moment they passed away. A probate of some kind must be done to pass title from the estate to the heirs.
Thus, at this time the plot at the cemetery belongs to the estate of the deceased and to pass it to the correct owners a probate must be done. It is possible that an argument could be made that the graveyard should not have allowed anyone to be buried on the plot without a probate being done and determining who is the correct owner.
The graveyard could be sued for breach of contract, possibly, by the estate of the deceased and the daughter who disposed of or took the property could be sued by the estate as well since she didn't have the authority to do that. That would mean that someone would have to hire an attorney and then file for a probate and, after they are appointed executor, they would have to sue the daughter and possibly the graveyard as well.
You can find a lawyer to assist you by going to www.lawyers.com and in the section for Area of Practice enter Probate Law or Civil Litigation. Either of those will have the skill set you need.
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