mother blackmailing for property under influence of her family

We are a hindu family. My dad had bought a plot and built a home taking housing loan too. He had registered the land an house in the name of my mother. My dad has been the one to pay for all taxes and bills for the property. My mother has slipped into a depression and regulary threatens to harm herself and also keeps saying that the property is in her name and she will send my dad out. Her long lost cousin has suddenly appeared and makes uninvited visits. My dad ails from heart trouble and is worried what will happen after him....and that mom should not fall prey to someone in a weak moment. How can my dad get the property transferred to himself legally...given that he is the one who earned and paid for all of it?