The facts lack details and without knowing such facts, you can not expect precise guidance. Your query "my family somebody has entered an unregistered will." is vague and ambiguous. Who is that somebody? Who has executed such will, when and in whose name and what are the relationships? What exactly is the present issue and status of such property?
1. There has to be two witnesses atleast proved to be present when the will was made. 2. If natural successors have been deprived, there should be reasons written in the will as to why did the deceased deprive them. 3. Signature and handwriting will also be considerable points.
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