My brother owns our childhood house through an LLC. Our parents totally paid for the house so he has no debts on the house but the challenge of maintaining the house and property is a huge responsibility. He cares full time for our mother living there. He takes her to medical appointments as well as other places, handles her medicine, what she eats or can't eat. He does have a granddaughter who lives upstairs help our mother with bathing once a week. He controls all her money, basically $2000US/month but still demands money for her care. He isn't willing to be accountable for the costs of her care so I really don't know how much he spends on her needs. She does have short term dementia but recognizes me and others and can carry on conversations. She is still mobile using a walker and able to take care of basic daily needs. Oh yes, she is 101 years old. My brother is retired on SS himself but apparently needs to supplement his own needs. He isn't able to work much because of caring for our mother but also has his own health issues. He has not been good with money and in years past received money from our parents when in need. Unfortunately for him our mother divided the rest of her savings up equally between her four living children. Apparently he needed money was the problem but I think he may have been surprised she shared the money equal between siblings. He isn't willing to talk about our mother's caregiving. He won't let me or others have input regarding her needs. He took away her Alexa machine in her room so I have no direct way to connect with her since I live a distance from there. Our mother would like the Alexa in her room. She basically has given complete control over decisions to my brother who doesn't include her desires or the wishes from the other family.
Your brother may be justified in getting some of that money back to pay for her care, including compensating him as a caregiver.
But, he should be able to provide an accounting of exactly what the expenses are and where the money is going. If he has a history of not managing money well, then there will be no end to his requests for more. People who don't manage money well think it can be solved by getting more from someone else.
If your mother dispersed all of her savings more than 5 years ago, she may qualify for Medicaid assistance. If her income is insufficient to pay for her care needs, then Medicaid will help to pay, including paying a family member as a caregiver.
It sounds like you are more concerned that he is taking complete control and not allowing input from other family members.
There are two very different possible scenarios at play:
1) He could be taking advantage of her, or abusing, neglecting her.
OR
2) He, like many family caregivers, feels resentment when other siblings want a say, or to criticize, but have not offered any real help, whether hands-on or financial.
So often, family members are critical of the one who is doing all of the work. The caregiver needs real support from family. Unless they are proven to be completely incompetent or abusive, in which case, a call to APS is in order, or the family could petition the court to have the person removed from their position, and have someone else take over. Most family members don't really want to take over the job though.