My BARNHILL data is somewhat limited. Sherena *Elizabeth* BARNHILL (my ancestrix) and your Margaret BARNHILL were daughters of Abel BARNHILL and Anne S. (--?--). Elizabeth (age 13) appears in their household at the 1850 US census of Benton County (Sugar Creek Twp.).
Elizabeth BARNHILL md. David Cunningham BOYDSTON, s/o Thomas BOYDSTON and Hannah CUNNINGHAM, c1853 probably in Benton County (I could not find David on the 1850 US census but his brother, Thomas J. BOYDSTON, was living with his future father-in-law, Abner JENNINGS, a few houses down from Abel BARNHILL).
David and Elizabeth (BARNHILL) BOYDSTON had the following children:
1. Abel B. (Barnhill?) BOYDSTON, 1854-1936; md. Susan Elizabeth ADAMS, c1886
2. Unity BOYDSTON, 1856-1940; md. John Polk HOWELL, 1876
3. John BOYDSTON, c1859-1860
4. William B. BOYDSTON, 1861-1927
5. David BOYDSTON, c1863-?
6. Amanda E. BOYDSTON, 1866-?
7. Mary A. BOYDSTON, c1869-?
8. Henry BOYDSTON, 1870-1957; md. Marida WESTFALL, 1905
9. Sarena E. BOYDSTON, c1873-?
10. Ruth BOYDSTON, c1877-?
This family was residing in Williamson Co., TX in 1860; Wise Co., TX, in 1880; and Stonewall Co., TX, in 1900.
A published inventory of Stonewall County's Swenson Cemetery shows that David C. BOYDSTON was b. 18 Oct 1828; d. 28 Aug 1912. Elizabeth (BARNHILL) BOYDSTON was b. 17 May 1834; d. 19 Jan 1916.
I wish I knew more, but this family has thus far resisted my efforts to do so.