What are the moral and legal obligations for adult children in caring for a parent with early Alzheimer's/memory loss?

What are the moral and legal obligations of successful adult children (living in the same town) in caring for a single parent living alone and in denial about early Alheimers and.memory problems? How does the above change after the adult children (40-50 yrs old) get a court action giving them conservatorship of their 71 year old single mother who lives alone in the same town? Except for current time memory loss and some questionable judgements, parent is in robust health and verbally and socially adept.