It turns out (proven) that the wife of John Naill, Mary "Polly" Barkley/Barclay and the wife of Samuel Naill, Elizabeth "Betsy" Barclay, were indeed sisters. These two Barclay girls Mary & Elizabeth, were daughters of Felix Barclay and Pricia "Pricey" Brock who were married in Knox County, Tennessee in 1799. So this, added together with a few other circumstances, stregthens my suspicion that my g-g-grandfather John Naill, born 1786 N.C. and Samuel Naill, born abt. 1782 Ireland?, were actually brothers. Also, I may have found two other possible siblings of John and Samuel Naill and they are - Margaret "Peggy" Nail, who married John Sloan Steele in Mecklenburg Co., N.C. on 7, Dec., 1812, bondsman: John Steele, witness: Isaac Alexander - Elizabeth Nail, who married George Walker in Jefferson Co., Tn. on 2, Dec., 1815, bondsman: James Walker. Now, Felix Barclay had stipulated in his 1809 will that when his youngest child had reached a lawful age that a certain portion of his property (land) was to be sold and specifically this property was 94 acres at Swan Pond Creek in Knox Co., Tn., that Felix had purchased from James Brock in 1804. When Samuel Naill traveled all the way from Madison Co., Tn. to Knox Co., Tn. to marry Elizabeth "Betsy" Barclay, the marriage bond was dated 8, Oct., 1828 and then twenty days later on 28, Oct., 1828, Samuel Naill and Elizabeth "Betsy" Barclay had to sign an indenture agreeing to the sale of this same 94 acres from the estate of Felix Barclay to Peter Merriman. This particular document was witnessed and attested to by John Sloan Steele and George Walker, the husbands of Margaret Nail and Elizabeth Nail, respectively.