I have a William Fabious Mitchell born about 1842, who married Mary Jane ____, which may be the same as your William Fabius Mitchell who married Mary Jane Foster.
If they are the same his parents were Fabious L. Mitchell born March 9, 1803, Amelia County, VA, died March 21, 1868, Floyd County, VA, buried Wright Cemetery, Floyd County, VA; married Mary A. ____ born July 9, 1815, Bedford County, VA, died March 4, 1887, Floyd County, VA, buried Wright Cemetery, Floyd County, VA.
The 6 children of Fabious L. and Mary A. Mitchell are:
1. Thomas J. Mitchell born about 1838 married Martha Howery
2. Josephus A. "Cephas" Mitchell, born December 22, 1840, died March 13, 1891, Floyd County, VA, buried Wright Cemetery, Floyd County, VA married Elizabeth C. Rutrough.
3. William Fabious Mitchell born about 1842
4. Alexander Mitchell born about 1844.
5. Susan Mitchell born about 1846.
6. Martha A. Mitchell born March 31, 1849, Floyd County, VA, died December 8, 1916, Floyd County, VA; married December 12, 1871, Floyd County, VA, Andrew James Rutrough.
If this is the same person - I will check the spelling of "Fabious" on Fabious L. Mitchell's tombstone for you. Of course the spelling on his tombstone could be incorrect. I have helped clean the Wright Cemetery many times and have 2 brothers, a sister, father, grandmother and many other family members buried there.
Also I would appreciate information on William Fabious Mitchell and Mary Jane's descendants.