Can a property be transferred on behalf unsound mind person?

My father expired few years ago and my mother is neurological patient and in her current state of mind she is not capable enough to make sound decision. She has a property which belongs to her name through Nomination after father's death. In such case if we the children plan to make sale of the property what is the ideal way in doing it on behalf of our mother who cannot make the decision on her down. We are 4 children in total.