Believe it or not, the “springing” power of attorney you describe was removed as an option in Florida a couple of years ago, which is unfortunate. But good on you for getting the family to stick with the plan. That is over half the battle.
We got her back in a week, and over the last year she's been with us. Our doctors say she is fine, just mild dementia. Our lawyer provided them copies of multiple documents which stated my wife as trustee and caregiver, several times since 1992. We are well off, while one sibling is in bankruptcy and the other has no money. For us, it's not the money but preserving mom's independence. I wouldn't want my freedom taken from me. Make sure evil relatives don't to it to you.