Has your mom been dx with dementia? If so, has she been deem incompetent? How old is mom? What is mom's living situation, living alone, living with you or someone else? What level of care does she need?
What kind of legal are you speaking of? Are you her POA? Are all her legal documents set up? Hopefully so, if she is incompetent you will have to pursue guardianship.
If so, has she been deem incompetent?
How old is mom?
What is mom's living situation, living alone, living with you or someone else?
What level of care does she need?
We need more information to help you better.