Oh.I see.You are saying your Thompson had a son William Sylvestor and so did a member of the Habersham Allens that moved to Union.Well the two clans did look related before and that naming would add weight to that theory.Maybe there was a William Sylvestor Allen back where the two lines branched.As I mentioned, there is evidence to suggest Thompson's grandfather was named William.
"In 1866 Thompson was in Macon Co. NC".How do you know?what was the event and proof?Recorded marriage?"but he moved to GA by 1876 because that's where William Sylvester was born."Probably, but if the birthplace is from census records they are often wrong.I've had ancestors with 4 different birth states listed in 5 censi.So, you need to find Thompson in 1870 and you know where to look, but keep in mind not everyone in an area always made the census, especially when things were in turmoil just after the war.I can't find many of mine in 1870.But look and when you find him get the names of neighbors for at least 10 houses on either side of him and any other know relatives.Same goes for 1880, but he could have gone west by then.Do you know where your people were from 1880-1920?you may have to work from the ends to the middle.
"In the 1860 census of Towns County George is listed with wife Rebbecca..."George Washington Allen was listed in 1850 and 1855 censi of Union Co. by Barbary (Edwards) Allen, undoubtedly his mother.Do you have census data for the Allens in 1860 Towns? Please post if so.