I find interesting that there were three Sweeten Households in 1870 Fulton County census, have you checked to see if there is a tie to one of those familes, John, My GreatGrandfather age 53-58 is listed at the Southfork Twsp, Also there is J.E. age 47 listed at SouthFork Twsp, he is the right age to be an older brother, and J.W. listed at Myatt Twsp age 24 or 26 might be a nephew.