I'm descended from Samuel Oxford Sr. and Unknown Wife, through their son, Samuel Oxford Jr. and wife, Bathsheba Barrettt, through their son Abel Oxford and wife, Edieth Rogers, through their son William Claiborne Oxford and wife, Louisa Ramsey, through their daughter, Mary Jane Oxford, wife of Jonathan Jones Culwell. Mary Jane Oxford Culwell was the mother of my maternal, maternal, great-grandfather, William Claiborne Culwell.
Reading through your first posting again, Abraham Kuykendall sold land in 1805. You said he was married to a woman named Bathsheba at that time. Did she have a dower interest in the land, and have to agree to it's sale? If so, she was presented by him as his lawfull wife, and believed by the court, and witnesses to the sale, to be legally married to him.
The 1800 census shows Bathsheba Barrett Oxford seperated from her husband, Samuel Oxford Jr., and living alone, as a head of family, with her four youngest children. The youngest two of those of her children fathered by Samuel Oxford a daughter and a son, were born between 1784 and 1790. Both would have been over the age of ten by 1810. In other words, Bathsheba Barrett Oxford had no children from her marriage to Samuel Oxford Jr. that were included with the four boys under the age of ten, ennnumerated with Abraham Kuykendall in 1810. His wife, Bathsheba, since he was a widower in 1803, had to have borne him, unless these were Elizabeth's children, four children in six years time.
A 1771 church petition shows Samuel Oxford Jr. with two "souls" in his family. I'm assuming the other "soul" was Bathsheba, and since they were apparently childless, they'd probably married around 1770/71. If she was between fifteen to twenty years old when she married Samuel Oxford Jr. she would have been born circa 1750 to 1755. That would have made her forty-nine to fifty-four years old when she married William Kuykendall, if she did. Since the 1800 census shows Bathsheba Barrett Oxford as over forty-five, this estimated birth date fits the minimum age she was reporting for herself in 1800. Given her probable age of forty-nine to fifty-four, it's quite unlikely, I think, that she would have been, if fertile at all, fertile enough to have borne four children in six years time.
As for her having grandchildren, I can't say that I know the death dates of all of her children, but offhand don't know of her having lost any of her adult children by this early a date. I'm fairly sure, but not absolutely certain, she hadn't lost any. That would mean she'd not be likely to have grandchildren living with her.
As for the Samuel Oxford Seniors and Juniors, it is confusing! We don't know exactly when Samuel Oxford Sr., father of Bathsheba's husband, Samuel Oxford Jr., died. We do know though that Samuel and Bathsheba Barrett Oxford's son, Samuel Oxford III, was an adult, married, and living on his opwn, by 1800. For that reason, it appears, by 1800, Samuel Oxford Jr.'s father was dead, and with his son being an adult, Samuel Oxford Jr. had become Samuel Oxford Sr.
AS for Edieth Rogers, wife of Abel Oxford, having been a daughter of George and Elizabeth Lawson Rogers, that's an assumption made by a Buncombe County historian. There's no documentary proof that I know of, and one of her grandaughters, although only one of many, claimed she was the daughter of a half Cherokee man named John Rogers. That isn't documented either though, and she's proven not to have been a daughter of Chief John Rogers, which is what her grandaughter first claimed. Her parentage is still unproven.
As for Bathsheba, I suspected she disappeared off North Carolina record by 1811 because she'd probably, I thought, moved on to Giles County, Tennessee, where most of her immediate family had moved. (Her daughter, Bathsheba Oxford Byler lived there, and Basthsheba Barrett Oxford's death date is recorded in her family Bible.) She appears on no record there though, so it's not certain she did leave North Carolina.
As for her being married to Abraham Kykendall, nothing's impossible! Still the few facts we have, while proving nothing, do argue against it. As follows:
1. There's no record of Samuel and Bathsheba Barrett Oxford having been divorced, or having petitioned for a divorce.
2. There's no record of either of them having married anyone else.
3. In the suit brought against his estate, following his death in 1811, she was identified as Bathsheba Oxford, which wouldn't have been the case of she'd been married to Abraham Kuykendall.
4. Samuel Oxford names no grandchildren in his will, written in 1810, certainly suggesting he, which would mean Bathsheba as well, didn't have any orphaned grandchildren.
If you still think Bathsheba Barrett Oxford might have been married to Abraham Kuykendall though, then it might be worthwhile to try and identify the land she was living on in 1800, and/or the history of the land Abraham Kuykendall sold in 1805. If she acquired land in a divorce, and remarried, her husband would have acquired control of any land she owned, but couldn't have sold it without her consent. Her son, Abel, did own land on Ivey Creek, and 1805 was the year some of the Oxfords started selling out, and moving on. It's a longshot, but if she was divorced, land records might give evidence of it.