Legal right of wife if husband selling off the only home (property)

Sisters(married) and one youngest brother(X), married with a mentally challenged daughter decided to transfer the only property (Very small) left by their father to their only brother's (X)name. The said property was sold and another property bought in the X name. One of the married sisters has been setting eye on this property and claiming her larger share had convinced the brother(X) and taken loan against the same property. She is now trying to force X to sell the property . X does'n work and plenty small time loans. How to protect the wife of X, as she has to support herself and daughter.