Benny Gordon said in one or two replies on the Abernathy forum that Samuel Vance Abernathy was a son of David Wilson Abernathy and Ruth Vance. They were living near Samuel at the time of the 1850 Mississippi census. It appears that David was born about 1767 and Ruth about 1779, both in North Carolina. By 1818 they were in Jefferson County, Alabama, and moved to Pontotoc County, Mississippi, in 1849.
Samuel Vance Abernathy and Eleanor Abernethy were said to have been cousins, but I don't show David as a brother of Eleanor's father, William Abernathy. To be second cousins, their grandfathers would have had to be brothers, but I don't find that, either.
Anyhow, if you can find David Wilson Abernathy and his wife, Ruth Vance, among your lists, along with David's parents (possibly James Abernathy) and grandparents, it would solve a mystery for me.
No, I haven't heard from Susan Kirk, but then my email address has changed.