The sister initially moved mother in with her and husband right after dad died. This was not discussed with siblings. Shortly, about 6 months, the sister's husband demanded our mother move back into her own house. There was nothing wrong with mother health wise. Months after that, the sister began to enable mother not allowing to do for herself. Mother was a vibrant church going woman and very strong in her character ways. She had no debts - house paid for and a car which I mostly help to pay for.
All siblings (2 brothers and me/eldest sister) would visit mom and make sure she was fine. I must tell you that 2 of the siblings live out of town (I am one who lives out of town) and have for 40 years. My established job/business is out of town, my church, etc. But it is nothing to go and visit your mom. There is nothing we wouldn't do for our widowed mom. Mother loves all her children, but something was changing. Mother , age 68 became very dependant. The sister felt that she should be on mother's checking account to pay mother's bills. Mother receives SS and the only bills at the time was phone bill (maybe $27.00 and water and electric bill). The sister decided to make herself POA. Not a problem as far as I was concern.
A few years later, the sister felt the need to inform me she needed help with mother's expenses such as food and medicine. Mother became diabetic. I decided to move to live with mother and help out. When asked to see the budget, the sister stated, there wasn't a budget. I thought my sister and I were close, but I found out through mother that my sister and her husband were going on cruises, etc. The sister never mentioned that to me.
I was with mother for a few months and had to return to my home and responsibilities. Unfortunately, things became worse. Mother became isolated, not wanting to go to church or visit anyone. That was a clear sign of depression. But the sister with POA decided that she couldn't make mother get out, so she continued things as usual. I could see resentment developing with my sister as she would talk about what the other siblings were not doing. Heaven only knows what she might have been saying about me. By the way while I was living with mother, I saw that the sister had taken out numerous insurance policies out on mother - she was the beneficiary. She tried to justify that mother needed the 4 or 5 policies. I realize that was where some of mother SS was going. I did not think she needed them, but the sister being POA was in command. But somehow she was still asking us to help pay for food, taxes (first of the year) on mother's house.
The sister had mother to move into her house with her and husband. By then mother was totally dependent with aggressively developing dementia and alzheilmers. When one takes in and becomes a caregiver, there are going to be changes,.... often times drastic changes. But the sister was not communicating, until it became too hard to handle. We all wanted to be there in the beginning and still do now, but we want transparency - and not just give you information as she feels you need to know.
Fast forward, much resentment has set in, and the sister has decided to allow people to move into mother's without discussing it with siblings; we don't know where mother's care is; The sister has rented storage places to put mother's things without informing any of us; the person living in mother's house is not paying rent. We are all very concern because the sister says it's none of our business. That's between she and mother. Mother for the last 7-8 years had had memory issues.
I suspect the sister isn't being truthful, does not feel she has to discuss anything with us and I fear that mother is being taken advantage of.
As for mother's car; no one knows where it is.
Now if your mom told you sis is going on cruises, I would take that with a grain of salt. Our mom says she goes to Europe every Saturday; she is actually watching PBS. Find your mother and visit her, but brace yourself for someone who may not know who you are. Anything she tells you may not be connected to reality. I knew a woman who kept telling siblings "Your sister makes me sleep in the garage!!!". She was hallucinating, but the statement caused a tidal wave of complaints and hard feelings. I would be better to get everyone together and make the final plans for your mother, now is the time.