Well, happy Thanksgiving!? Sorry these issues burden you today and I apologize for this necessarily vague answer. The issues here depend on the ownership of the property (was is community or separate) and the terms do the deceased husband's will. The will may purport to give to the son property belonging to the widow, so the will may not be what it seems. But any decent answer requires an understanding of the assets and examination of the will at issue. Please have your mother in law consult with a local attorney.
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I agree with Attorney Pyke. Your MIL should probably see an attorney to determine what her rights are and to see what her options are.
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