It seems to me that I remember reading some time ago that the McKenneys of this region of North Carolina were related to Daniel Boone. I can't for the life of me remember what the relationship was: Daniel's mother's family? His wife's family?
If you check out Daniel Boone bios you might find a clue. I'm sorry that I can't be more specific, but my reference books are all packed up and ready for a move.
Good luck. And please post anything you find about this family here, please !