Phelps of Georgia and Texas

I am doing research on my paternal family line:

Me - Carla Phelps Wert, b 7/11/1940 Eureka CA – married to Barton Joe Wert
Father - Carl Benjamin Phelps, b 1917 Arcata CA – d 12/8/1995 Whitefish, MT - married to Helen Marie Nelson
Grandfather - David Edgar Phelps, b 1883 Burleson Co TX – d 1961 Eureka CA - married to Bertha Ischy
G-Grandfather - John Arthur Neal Phelps, b 1849 Pulaski Co GA – d 1888 TX - married to Nancy Keese
GG-Grandfather - William Phelps, Jr., b 1814 Charleston SC (?) – d 1875 GA or TX - married to Christian Rachel Buchan
GGG-Grandfather - William Phelps, Sr., b about 1773 ENG (?) – d 1828 GA (?) - married to Sophia Lee

I have hit a roadblock with William Sr. and his wife Sophia Lee -- if anyone can help I would be very grateful !!!