Money was taken legally out of my mothers, who has Alzheimer's, checking account by a family member who now refuses to part with it. Advice?

I'm confused.  Your post title, segueing into the explanation, reads that "a family member who now refuses to part with it for care-giving an (sic) other expenses."

Perhaps I misunderstood, but the including of "for care-giving" inferred this person was in fact performing some type of caregiving.   Is that not so?

How do you know about this, and for what was the money used, since it apparently wasn't caregiving?

Is this person a joint co-owner on the account?   Has your mother executed any DPOA or POA that would allow this person to make payments on her behalf?

Not sure what you mean by taken legally. How did they get the money? Did your mother give it to them? Did they have a joint account and this person helped themselves, which would be legal but possibly unethical. Did the person say they were taking the money to pay caregivers and then didn't? Not enough info here.

If the person got the money legally, they can keep it. They wouldn’t have to pay other caregivers.

If the money was taken legally as you say, what do you want that person to be held accountable for? The money was for caregiving and other expenses according to you. Surely they should have been compensated for caregiving, it’s hard work!