Can one question or oppose an Enduring Power of Attorney?

My sister is experiencing Early Onset Dementia and I have just been told by her son that the daughter of my sister has applied for an Enduring Power of Attorney regarding my sister but my sister is still married and I wonder what on earth is going on.
I have no idea if my relationship as a brother offers a legal right to question such an application or if the son of my sister has such a right. It might just be that I am being over sensitive but this situation does worry me a trifle.

How advanced is her dementia?
Has anyone done a Mental Capacity Assessment?
She has to understand enough to be able to grant anyone the power to represent her!

A PoA is raised by the Donor (i.e. your sister) and they name who they want as Attorney(s) - usually a close relative. PROVIDING that they, the Donor have mental capacity to understand what they are doing. If mental capacity is lacking then a close relative can apply to the Court of Protection for Deputyship to handle their affairs. This 2nd option is a lengthy and expensive process and will be overseen/supervised and, if finances/property are involved audited by the Court of Protection.

When a PoA is applied for the nearest relatives of the Donor (i.e. your sister) should be contacted to ask if they have any objections - in my Mother’s case this included her nephews and her grandchildren (my sister and I were the named Attorneys).

The following links are to the .GOV website pages on Power of Attorney and Deputyship

Speak with your sister, ask her, she might think it’s an age thing and wants someone younger in case husband gets dementia too.

Tell your sister you want to be a POA as well, there can be more than one and you share the responsibility of looking after her best interests and if one is on holiday the other one is there to deal with things.