His gravestone says 1873 - 1929, but I cannot find a death record for him.

Either Mary’s date of birth (from death and cemetery records) or her parents’ date of marriage (from Gary D. Lewis) may be wrong, since together they have her born 14 months before her parents married. Unfortunately, there are no Rowan County court records for the 1870’s. The 1880 census listed her as age 4, which would be consistent with a birthdate in 1876, but census ages are often only approximate.

Gary Lewis’s charts also give her name as Mary Ellen, but the consent note for her first marriage calls her Mary Liz.

She is not buried with either husband, but instead with her parents. (Nathan Riddle is buried alone, and William Henry Dehart is buried with his first wife Sarah Ellen Clark.)

Rowan Co. Marriage Register Book A, p. 52, records marriage of Nathan Riddle and Mary E. Brown on 6 Oct 1892 at Comodore Riddle's. The marriage bond is in book 1, p. 99, with a consent note attached from Commodore Riddle, witnessed by D. K. Jones and John B. Brown, giving consent for his son Nathan to marry Mary Liz Brown.

Nathan and Mary may have been divorced, because she remarried to William Henry Dehart in 1926, but Nathan’s gravestone says “1873-1929”. On the other hand, sometimes stones erected years afterwards by children or grandchildren of the deceased will have an incorrect death date.

I cannot find this family in 1910, nor any other Rowan Co. Riddle family, nor many of the related Jones families, even doing first name searches. I suspect that some entire enumeration district may have been lost.

1920 census of Rowan Co., Ky, precinct #9 (Wagoner), lists as family #12/13:
Riddle, Nathan, 47; Mary, 45, wife; Arthur, 20, son; Jossie, dau, 17; Nettie, dau, 15. All born in Ky.