If your father is receiving royalties there may be no need for a probate of your mother’s estate at this point. Your father can do things to ease the inheritance to the next generation by deeding his interest to his trust (if he has one), if not he can create one or a simple mineral trust, another option may be a transfer on death deed. But you will need the legal description.
Unfortunately, Caddo county does not have any online search capabilities in order to trace the ownership. Perhaps the abstract company would share the legal description. It would also be interesting to know if there was an affidavit of heirship, deed or other instrument filed whereby your father received or claimed your mother’s interest.
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