Out of the blue my sister has demanded my mom's car that my son has been driving with my mother's permission for 2 years. My sister and I both are POA of mom's affairs. Why she suddenly thinks she is entitled is beyond me. She lives out of state and does virtually nothing to help while my son lived with my mom for a period of time to help care for her, now lives with us and I handle all of her finances, trips to the dr, etc. Thoughts? Advice? Can I stop her? I should also state that at this stage, mom is suffering from dementia.