My sister has dementia but is still able to understand what is going on. Her daughter-in-law is presently POA, but her husband (sister's son) says he is in control. My sister would like to add someone additional, not other children, to POA for her security. He has told her he wants her house then says he is not serious. He is good to her but has a very strong personality and hard to disagree with. I am her sister and I know the siblings have the control, but she has asked for my help. I do not want to make a difficult situation worse so just support and visit her taking her to my house from time to time. She does not want other siblings so I have suggested maybe a close friend of hers. Can someone be added to POA.
Also, it is NOT a good strategy to assign some as PoA who is the same or similar age as the principle. That person will get old and have problems, too.
And, if you're getting all your info from your sister (who you said has dementia) then she may not be giving you accurate information... especially about the house issue. People with dementia develop paranoia that can get progressively worse.
Finally, who's to say another non-relative PoA won't want the house, too. Elder financial abuse happens all the time. Sister could consider adding an attorney as another PoA, but again... I wouldn't.
One POA. Choose wisely and well, and name a secondary POA to whom duties pass if the #1 POA has to bow out.
However, here is the "rub" so to speak.
It is generally accepted that the POA is one person that you feel will act on your behalf, the way that you would if you were capable of making your own decisions, that you trust to act in your best interests.
Sounds great.
When you start naming two or more people - to be CONCURRENT POA or SHARED POA - rather than SUCCESSIVE POA - in other words named in order so that if POA #1 either can't or won't serve, the next person in line becomes their successor - you could unintentionally be creating problems.
Initially - when we first looked at FIL's POA documents - we thought that he had left DH and SIL as joint/shared POA. Which actually would have been ok for the most part because THEY agreed on his care. With one glaring exception. HER DH. He had ulterior motives that, while not nefarious, were self-serving. And not in FIL's best interest. And he holds very strong sway over SIL. That when he thinks is needed - he leans into VERY HARD.
So if your sister is going to redo her POA - I would strongly encourage her to consider the way she has it worded. I wouldn't suggest that she have them as joint POA if she suspects that her son is going to exert undue pressure on the other person/people to do things his way. Whomever is in that position needs more power than him in that case. If that is the case she should name them primary POA, and then DIL as secondary.
If she's not legally or mentally competent, it doesn't really matter. Nothing can be changed.
Recognize that have TWO operating at the same level of POA rather than as alternative when one cannot function, is VERY Confounding and often an utter mess of argument.
In my humble opinion that doens't work well.
Get the advice of an Attorney.
Only your mother can revise her POA.
It is a difficult mess in that accounts in banks and other entities are already set up.
You need to know
A) if mother still legally competent to do this
B) if this is at all a good idea
Get options legally. Good luck. Hope you will update us.