Unregistered will

My father wrote a will while he was alive distributing his property to both of his sons. He has three daughters who are married. But this Will is not registered. To get the property in the name of his sons, what is the procedure? Is the unregistered will valid? Will the daughters have the right to approach the Court of Law at any time? The property is not ancestral. It is my father's self earning. Kindly guide us in the matter.