The power to sign dissolution papers would depend on the power of attorney - unfortunately exactly the information you don't have. If I was advising the daughter I would recommend that she apply for a conservatorship of her mother's estate and for a specific power to dissolve the marriage. Then it would be up to your father-in-law to determine if he wanted to object.
Best to you and your family.
This raises a very interesting issue. Whose “emotional reasons” are we talking about? A conservatorship would provide the daughter with power of decision making for her mom. I would be very surprised if the power of attorney contained an expressed power to enter into a dissolution proceeding. What does the husband think about all of this? Unfortunately, attorneys will probably have to get involved.
Whether or not it’s a waste of time and money is better answered by your father in law consulting an attorney.
Best of luck to you.
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I do not expect the POA agent may not sign the court papers. However a "GUARDIAN AD LITEM" can be appointed and is less expensive than a conservatorship.
Here is a sample of one form use to have a guardian appointed. The Guardian Ad Litem is only guardian for the court case.
The Guardian must use a lawyer, and may not appear in court Pro Per.
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