I've done some research and show Anna Hopson married to James A. Brooks, a blacksmith b. 8 Jul 1860 in Campbell County, Tenn., and d. 28 Mar 1917 in Claiborne County, Tenn.
His father was John Jasper Brooks (1835-1901) and mother was Mary Heatherly, (1835-1876).
I don't show any of Anna Hopson's children as being John Fletcher Brooks. But, I could be wrong on this stuff. I would like to know what documentation you have so far on your grandfather.
Marsha Brooks Guerard