Joyce, My connection to the Singletary family is through my 4th G-Grandmother Sarah Singletary daughter of Joseph Singletary and Mary FitzRandolph. She married William Bryan.
Williams brother Nathaniel had a daughter Sarah Bryan that married John P. Singletary in the early 1800's. Thats as close as I can get to your request
The Public Library at Elizabethton, N.C. has a large collection of data on the Singletary line. May I suggest you contact them? Sorry I am not more help.