can a joint tenant,not tenants in common, but with the right of survivorship sell thier undivided interest in real property?

My mother deeded her property to three of four children in 1982. We all recieved a will and a hand written letter from my mother in 1984 explaining what she wanted us kids to do in the event of her death. For over twenty years all of us kids new that she had deeded it to us yet none of us ever acted as if we where the owners. We all new that it was not really ours untill my mother and father had passed away. In 2004 my mother passed away leaving behind her husband of 50 years. Less than a mounth later my oldest brother (out of spite ) sold his undivided interest to a total stranger with a special warrenty deed for one dollar. My brother did not tell anyone that he wanted to sell or that he did sell. We have been trying to reverse the sell for the past 6 years and let my father live out the remainder of his life in his home of 50 yrs. Recently due to the harrassment from the new owner and a judge that refuses to protect my father, my dad has had to leave his home. Keep in mind this man refuses to work anything out with the other owners or to let us buy him out or any type of reasonable settlement.