My evil sister basically took mom from home because brother had Covid19, and is not wanting to release her or allow visitations. Advice?

Desperate1932, what jumped out at me was the changing of the Deed from your Mom's name over to your name. When one does that, when the time comes to sell the house, the "basis" for calculating Capital Gain goes all the way back to when your Mom had purchased the house. It you don't live in the house then it becomes an "investment property" which is a different ball game tax wise.

If the Deed is in Mom's name and you inherit the house, when the time comes to sell, the "basis" for calculating Capital Gain goes only back to the day that you inherit the house. Double check with a Tax Accountant/CPA.

As for getting custody of your Mom, you may need to consider Guardianship. As mentioned earlier, contact an Elder Law Attorney.

Sounds like quite the mess. It's unfortunate when siblings act like such idiots and do not have the parent's best interest in mind. Not sure how to advise me since this is a bit confusing and complicated. Call an eldercare attorney?

This is much to messy for me to even have a clue what is happening or should happen. I am sorry. Family trauma and drama is very hard on an aging elder. Back in the days when the "Saints" were dying some of the relic seekers pulled stuff off them a bit before they were dead. That's what all this reminds me of when it comes to our helpless suffering elders, who are losing everything a step at a time, including dignity, and then must witness something like this.