I didn't find a tombstone for Gladys Tannehill listed in Defiance County.These are the tombstones found at the Old Forest Home Cemetery read by the Defiance Co. Genealogical Society.
Columbus B. TANNEHILL d. 20 July 1851age 1 yr 10 mo 29 d son ofA & E Tannehill ElizabethTANNEHILLd. 09 Mar 1870age 19 yr 5 mo 21 d wife of A Tannehill Adamson TANNEHILLd. 03 Apr 1877age 61 yr 9 mo 2 d Ella TANNEHILLd. 09 July 1881 age 22 yr 9 mo 2 d daughter of J & M Swilley: wife of C. V. Tannehill Dr. Charles V. TANNEHILLb. 12 Oct 1854 - d. 22 May 1917 son of A & E Tannehill C. V. TANNEHILL 1852 - 1917