I agree with my colleague and changed the practice area from real estate to probate.
This is a question for a probate attorney - who would need to see the deed and information regarding other potential heirs of your father's estate.
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I agree with Mr. Perry. I would add that, under the bare facts you mention, it does not appear you have any rights to the property in his girlfriends name. You need an attorney to review title documents and any will or trust that your father executed before you can determine if you are entitled to anything by virtue of your father's death.
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