I had to quit my job to do this. In her will it is stated that I have lifetime rights to stay in the home. Can my siblings sell the house to pay for my mom's nursing bills before she passes away?
You need to consult with an elder law attorney. A will does not go into effect until after mom passes. Siblings may want to honor mom's wishes, but care must be paid for somehow. If she goes on Medicaid then the house can be kept. Medicaid allows the family caregiver to remain in the home and may waive liens that are usually placed. If mom is able to self pay for a time, she will have more choice of the facility chosen.
Very helpful, and as you implied, siblings may be concerned that some homes do not take Medicaid pending, and somehow has to pay for NH before Medicaid comes through. As you said, wills are for disposition of property AFTER death, not before
Is your mother demented. If so it is too late to change her will. As to whether they can sell the house a lot depends upon who has the POA for her, and how that POA is written. They may be able to sell the home to pay for Mom's care. Is this a will or a trust? It would be good if you could take this document to a lawyer to have it checked along with any documentation that designates your Mom to suffer from dementia. So much depends upon state laws and how documents are written. Best to check legally rather than our own opinion here.
See that attorney.