I too, would love any SWEAT information you have for WARE or PIERCE County. My Mary Etta Sweat married Charles Wesley Andrews in 1873 in Ware County, so I don't think she could be the daughter of William and Martha, but possibly the sister of William? I found Mary E. SWEAT listed CENSUS YR: 1860 TERRITORY: GA COUNTY: Ware REEL NO: M653-140 PAGE NO: 146
REFERENCE: Enumerated 4th July, 1860 by Wm. H. Thomas
She is listed as the daughter of Thomas and Lucinda SWEAT. However, I don't regard this as unequivocal proof of her parentage because Mary E. was such a common name, however it's a good start.
Please send any info you have to firstname.lastname@example.org
, in return I will try to dig up the census listing and e-mail it to you complete with siblings.