Another thing that made me think these Adairs might be closely related; LEWIS BOSEMAN is enumerated just after ELISABETH ADAIR in the 1820 Pendleton County, SC census. Elisabeth's spouse, Rev. War soldier ROBERT ADAIR removed from VA [apparently Augusta Co.] during the revolution.They joined many friends and family in Pendleton. Maybe the Boseman's came from VA also.
Other Adairs in Pendleton SC in 1820 were: JAMES ADAIR, 16-26 living with 13 others including a female 45+ [perhaps mother-in-law or mother of James] JOHN ADAIR, 26-45 living with 4 others including a female prob wife, 16-26 WILLIAM ADAIR,JR., 16-26 and wife 16-26 [enumerated next to John] WILLIAM ADAIR, 45+ and wife 45+ Maybe this William [perhaps a brother of Robert, deceased] is the father of James, John and William Jr.. There was a JOHN ADAIR, killed in the war who may also have been Robert's brother.Elisabeth is shown living by herself with 12 FREE Colored persons and one slave.Her family had moved on to Georgia. She died in 1822.