If my father died, mother is still living…and a sister is claiming she has power of attorney, how do I make her PROVE she IS in fact POA?

If it turns out she isn't the PoA, then what? Is she suspected of theft or fraud? You don't really give much detail. If I were in your situation and you actually have some suspicion or proof of theft/fraud, then I'd consult with an elder law attorney (but do not tell sister this) to see what is advised. Laws can differ by state, so that's why you have to talk to a professional for your mother's state.

FYI even if she is the PoA it usually isn't in effect until there is one or more medical diagnosis of incapacity (depending on what is stipulated in the PoA document).

I am assuming that your Mother is incapable of speaking to you about this? Because the simple answer would be to ask your Mom if your Sis has POA.
If your Mom is suffering from dementia, what concerns do you have about POA? Do you suspect your Sister of fraudulent behavior? Of embezzling funds? Of doing an improper job?
When your Father died was your Sister ALSO the executor of his will and estate?
If you have reasons for concern (you haven't told us any), then do open a case with APS for wellness check on your Mom, let them know you have concerns, and let them know what those concerns ARE. Then provide any and all proof you are able to APS. While they will not come back to you with ANSWERS they will come back to the reporter to say they either did or did not find reasons for concern.

If sister does not have an original POA document nor can a copy be found, check with your mother's bank(s) or other financial institutions. Check with the attorney who may have drafted the POA. Check in your mother's papers. It's a long shot, but talk to your mother's bank(s) to see if they can help you determine whether one is in a safety deposit box. Without authority, they can't let you in, but they may have some ideas,

Also determine if your mother has in fact been diagnosed with Alzheimers or some form of dementia and is not COMPETENT. Even Alzheimers patients can be considered competent by the courts if they have lucid days. If she is assuredly not competent she cannot sign a new medical or financial POA. Unfortunately, the next step is to petition the court for conservatorship/guardianship. This can be complicated and expensive. Your best first step is to consult with an elder-issues attorney. Do not go to any attorney. A consultation should not cost a lot.

A financial POA agent has a fiduciary duty which is recognized by the courts. It would cost money for an attorney but if it's worth it sister can be hauled into court and made to show that she has been taking care of her mother's finances properly and prudently. This may scare the pants off sister as she will probably have to hire an attorney as well. If neither wants to go to court, they could petition the court for permission to work with a mediator. If so, they could come to an agreement on how to proceed and then then the court could issue an order. I'm not sure about whether the court would go for a mediator but it's worth looking into because it can save money and might help mend some of the anger between the sisters.

Considering the lifestyles of your parents... what? What about their lifestyles, and what's lifestyle got to do with whether or not your sister does in fact have power of attorney for your mother?

The POA doesn't matter until there are decisions to be made. At which point, if she is to make the decision on your mother's behalf regarding, say, a facility or a bank or a realtor, your sister will be obliged to show documentation and won't be able to act without it. But are there decisions to be made now which other family members wish to make on your mother's behalf? Or are you only suspicious about your sister's management of the bank account?

My guess is that she is unwilling to show any documentation because she doesn't have any. My guess is that she is using the term POA very loosely, and basing her claim to have POA on her being named as a joint bank account holder with your mother and quite possibly believing that it works like this. It is in fact, of course, putting the cart before the horse, but you'd be astonished how many people say "oh, uh, yes, I'm POA" when actually they mean they are next of kin, chief grocery shopper, geographically closest relative, in the room when the forms are being filled in, or whatever.

I would at this point simply tell sister that you are certain she DOES have POA and is handling all of Mom's bills, documentation she is required to do meticulously, but unless she can show you that you will have to see an attorney, take her to court to produce documentation and POA or simply show you her POA document. That will make it clear to her there could be a big mess if she doesn't produce the documentation done by her Mom WHEN MOM WAS NOT DEMENTED.
If she doesn't wish to do this I would get an elder law attorney for the next move.

Tricky issue with the bank, because if sister is legitimately named on the account, the bank may have had no need to see a POA. However a bit of bluff might help. For example, tell the bank manager that sister is claiming to have a POA and the rest of the family doubt if it’s true. The bank should check if they have noted a POA (or these days probably kept a photocopy), to protect themselves against the chance of any action by sister which is not permitted without a POA . Can they confirm when sister was added as a name on the account, as it may not have been done when mother was still able to make legal decisions. And can they provide you with a list of what sister is permitted to do as a name on the account, but not permitted without a POA (eg close the account and transfer the balance to a new account in her name?).

Suggesting that they might be liable for something is the best way to get them moving. You might get some useful information out of it – even if just confirmation that ‘everything is OK’. It might stir up sister (who as CM said may just be assuming POA without understanding the formalities required). And it is something constructive that you have done if you do seek legal advice – more than just ‘we don’t trust her’. Keep notes of all conversations. Notes made immediately are have weight legally.

It’s probably the simplest and cheapest way for you to get something happening.

You need to see an original signed POA as proof. If she can not provide the POA, consider that your sister may be trying to defraud your parent.

LOOKING FOR MONEY, ARE YOU????

If she’s able. Your mother can change it and problem solved.

IF THIS IS FROM TODD AND JASON....YUP....GOT THE PAPERS

Proof?
Show me the papers!

You may want to consult with an attorney specializing in elder law, but if your sister has been caring for your mother (or overseeing her care) and is on her bank account, then she has gone a long way to establish herself as your mother's caregiver. Do you have any reason to think that she is not doing a good job?

Good luck. I went through the same situation. Mother clearly had dementia. Sister got her to sign POA. It will cost you thousands of dollars to fight it. You need to find a lawyer who also won't rip you off. The lawyers will rack up their fees and not care one iota about you. Wish I could help you. Justice will not be done unless you actively manage your case. I wish I knew at the start the corruption that is involved.

That information could be public record - check with your County or STate government about that. Certain POA's are public record, I'm sure of it.

POAs ought to be reviewed periodically because needs change.

When my son became ill and went into the hospital with metastatic melanoma at age 36, it had spread to his brain and they had to remove part of his skull to relieve pressure on his brain. Because there were so many tumors in the brain he was determined to be incompetent to make decisions for his own care and as his closest relative and without a health care proxy or POA, I was named to handle this. His fiancé tried to fight this and wanted full control and say so over everything but the courts wouldn't hear it. If I chose NOT to carry out my duties as health care proxy then the job would go to his sister, then to his uncle, then to other siblings then to the state but NEVER to his fiancé. I also was assigned POA for things that did not involve borrowing money, like applying for social security and medicaid for him. I also could not open bank accounts or get into his current bank account. Altho his fiancé had possession of his debit card and not only drained the account but overdrew it by over $1000. I tried to close the account and the bank would not allow me to do even that until after he had died and then not without a copy of the death certificate. POA's need to be very specific and often for a set amount of time. I had one for my son when he was in prison for 2 years so I could file his tax returns and draw the money for his children. It was very specific and had certain dates etc on it for these specific reasons to cover the time he was going to be incarcerated. They also must be notarized for both signatories

When we did our will/trust we named our POA's. First choice, and follow-up choice. I have the will sitting here in the office, the kids could all take and read it if they were so inclined. We did ask the girls if they would handle this task and they both said 'yes' and KNOW they are the POA's and KNOW that if this changes in any way we'll tell them.

I guess the 'proof' should be written down somewhere. Ask for it from your parents, and then from sister.

Do you feel she's abusing this power? I kind of look on being POA as being a huge nightmare, but I guess some people like it. My YB is mother's HPOA and he acts like he's her doctor. None of the rest of want to deal with it, so we just let him, but I know he's legally her Healthcare POA, so I don't fight him.

What's with your parent's lifestyles that make you feel your sister hasn't got the best interests?

Seems like there are too many unanswered questions, and since the OP hasn't come back to answer them, there's really not any way to give helpful advice.

From looking at the answers from OP and 'empathic' they might be battling it out on the phone, text message or maybe even in person. We might not hear from them anymore.

A POA can be revoked and a new one put into place. If you sister is on the bank account the she is an owner too. You mother can write a check. Things can be put into a living trust. You may need to spend a little money and speak to an attorney.

Good luck.

This issue comes up fairly often and I have enough curiosity about the answer that I did some basic searching online but nothing really comes up.

My money is on that the PoA doesn't have to prove it to any individual (as opposed to an entity like a bank or hospital, etc), unless there's evidence of financial fraud/abuse and they've been accused... but find it hard to believe this could really be the answer. I've emailed our family's elder law attorney and am waiting for his answer. I will post it when he responds.

if your sister is listed on mother's bank account, she is co-owner and no POA is needed, If there are issues and your sister is unwilling/unable to discuss what is going on then your best bet is probably to talk with an eldercare attorney

I had to get a lawyer. My sibling was on mom's accts. Told me I had no business asking questions, or knowing anything. Told me my parents entrusted her with poa/wills, bc I would spend their money and not pay their bills. Blah blah blah. My mother told me that wasn't true, She never had dementia. Tried to scare my mom about me as well. Tried to tell ger I didnt care. Couldnt eait for her to die. Not at all. Mom told me the lawyer said it usually goes to oldest child. She could have changed it, but didnt.
If you have ANY feelings something isn't right, no answers given, fishy things going on, get a didn't. Immediately!!!
My lawyer told me I should have never waited. Sibling up to all sorts of shenanigans. He said I waited too long. I believed her and had no proof of anything. Lied to me over and over.
You are entitled to see a list of assets that are given to the court when a person dies. I never got that. Of course your mom hasn't passed. You are also entitled to answers.
Took my sibling to court and found out all sorts of things. I won't go into but it was bad. Very bad.
So get a lawyer and she will have to show proof she is poa. And can get an accounting of things.
My mistake was I waited. Don't wait.

1. As an aside, she is foolish being on your mother's bank account. She should check with her tax advisor and/or estates attorney but I doubt she will.
2. Another question is was your mother competent when she agreed to put your sister on the bank account?
3. Are you talking about financial and medical POAs?
4.Are they durable POAs or springing POAs? Are they time- or subject limited? When did she sign them? If your sister can't answer these questions, that might tell you something. Of course, she will probably refuse to say.
5. I have to think you've done this, but look through all your mother's papers. She may have a copy or the original.
6. Ask your sister if she had the POAs witnessed and notarized. They don't have to be but the question might shake her up a bit.
7. Do you know the name of the lawyer or firm that might have drawn up a POA? Client privacy may be an issue but explain that you are worried about fraud (but only if you are).
8. I'm assuming you've asked your father. However, if he's competent, ask him to identify all her banks, any accounts she might have at any investment firms, the names of hospitals she's been in recently, and the names of any regular or specialty physicians she's seen. You can also look through her papers to identify any of these.
9. Does your mother have lucid days? Even some people with dementia have days when they are lucid enough to make their own decisions. This is a question for her physician or dementia specialist, I think. This could be a HIPAA issue though.
10. If the POA document exists, your sister may have given it to the bank where your mother has her account. The question about whether they can say whether it exists and names your sister as the agent is probably one of privacy. You could start by calling the bank and asking them. I've noticed that not all institutions necessarily know the rules or misinterpret them so if you get a no, consider checking with the FDIC. FDIC banks have rules about sharing a customer's information with an unaffiliated third party but they are complicated. You can check the FDIC site online, or call the FDIC (eek).
11. You can consult with an elder attorney who has probably dealt with this kind of thing before. An hour or less of consultation shouldn't be prohibitive.
12. Or, for a relatively small amount of money, talk to a lawyer versed in privacy issues. Ask about all financial institutions and HIPAA, eg. is a POA document considered Protected Health Information? Mention if you think your sister is stealing or committing fraud. This can affect privacy rules
13. If your father is competent, ask him if he will name you his financial and medical POA agent. Of course, you and/o he may not want to do this.
14. Try to find out if your father and mother jointly own any assets or property. For real property, you can check in your county's property records to see how their house is titled. If it's titled in what is called Joint Tenancy with Right of Survivorship, seriously consider speaking with an attorney. Of course, if she tries to change the title, she will have to produce the POA document.
15. Finally, there is no substitute for consulting with a qualified elder attorney. Put all your questions and any pertinent information together first.
16. Depending on your situation, you will want to make going to court to make her show that she has the POAs your last stop.

P.S. Does your mother have other estate planning documents such as a will, advanced directives, HIPAA release, and Do Not Resuscitate Orders? Just good information to have.

P.P.S. I've read the other comments and some people say that Waid 1435 isn't communicating anymore and has solved their problem. But I've left my comment up just to give people in the same seat some (not all) information.

Why is she refusing to show you the POA document?

Power of Attorney has to be registered in the UK. There must be a way to confirm
this is genuine with the government.

Waid1435: Perhaps more information is needed here, e.g. "considering the lifestyles of our parents" - this may or may not have anything to do with your query.

Is this your sister or your mother’s sister? If the latter and it’s ‘Empathetic’, there may be a question about her own legal capacity?

Is mom at home or at a nursing home? They make you sign a stack of papers there. They would know. Or if mom went to hospital for anything. You could ask them.