You state that "James also was the jurat on Robert Abernathy's 3 (Mary) will and was not on Robert Abernathy's 4 (Sarah) will because he drowned in 1785."
If this is the case, what is the relationship of James and Elizabeth Abernathy that conveyed a deed to Smith Abernathy in 1792 (Lincoln Co.,NC DB 16, 250) to the James Abernathy that drowned in 1785?
I am not a descendent, but am trying to piece together Rebecca Abernathy's ancestry that lived in St. Clair Co., Illinois and married Moses Farrar on 20 Sep 1817. One presumption is that she is a daughter of Robert Abernathy of St. Clair County, Ill., and that she died before her father's will written on 19 Sep 1826. However, there were a couple of other Abernathys in St. Clair or adjacent Washington Co., Ill. about the same time. It appears St. Clair Co. was a "staging area" for further migration into Missouri after statehood in 1820.