1. Neither your mother nor you can sell any of your father's properties without taking the grant of probate of the will from the Court, if probate is mandatory for execution of wills in your area unlike Delhi,
2. First of all file an application for the grant of probate of the unregistered will and send notice to all other legal heirs through Court,
3. It is not mandatory to register a will and the last will prevails upon all earlier will whether registered or unregistered,
4. In view of the above the last unregistered will of your father should be given effect of unless the other legal heirs contest the same and prove with evidence that the last will submitted by you is invalid for whatsoever reason.