I don't anything other than a Declaration of Heirship proceeding in court is going to clear title to this land. The way someone would "sign over" an interest in real property is a deed. But, you have to prove they are an owner first. That is what the Declaration of Heirship proceeding does. They are going to need an experienced probate lawyer.
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The date of death of each person involved in your question must be known to determine who owns how much of the land in question. A probate attorney needs to be consulted to determine whether a judicial heirship proceeding or an affidavit of heirship would be the appropriate alternative to clear title as well as whether an administrator needs to be appointed for any of the estates. Once the ownership of the land has been determined, if an owner wishes to transfer his or her interest to someone else that may done pursuant to a gift deed.
I agree with Mr. Clausen. Hire a probate lawyer.
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