I would have a lawyer take a look at this to determine if things are as you suspect them to be. Whether you need to re-open the estates depends on what the documents provided and how the property was titled. You also indicated that your grandfather sold the property. That would need to be reviewed to make sure that FULL title was not transferred instead of 50% like you believe.
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I'm not quite following your facts. What "current deed" is incorrect? Who appears to actually own your grandmother's undivided half interest? Was it a professional title search? Did granddad and grandmom have different heirs? Are you sure there was no "Certificate of Transfer" issued by Probate Court?
I would take this to a real estate title expert in the county where the property is located to determine if there is, in fact, a gap in chain of title and get title counsel's advice on how to cure. It is certainly possible that both states will need to be re-opened ... and that, depending on the value of the land, an Ohio Estate Tax return may need to be filed or amended, complete with penalties and interest.
Mr. Huddleston is an Ohio-Certified Specialist in Estate Planning, Trust & Probate Law, with offices in Columbus and Dayton, serving client families and private business owners throughout Ohio. He may be contacted directly by phone toll-free at 888.488.7878 or by email CLH@HUDDLAW.COM. Mr. Huddleston responds to Avvo questions as a public service to help educate and provide general guidance to questioners, but his responses are not legal advice and do not create an attorney-client relationship.
If you grandmother owned a 1/2 interest in the real estate at her death and the property was not disposed of in her estate, then the estate will have to be reopened for the property to be distrbuted to the proper heir.
This information is not intended, and should not be construed, as legal advice. I encourage those with questions to consult an attorney of their choice for guidance.