I don't have much on Emma Simpson.One of Ballard's granddaughters, Sylvia, knew his second wife was Emma Simpson and that Ballard and Emma had a daughter, Bertha.(Sylvia is 91 years old, still living, and has a remarkable memory of her family history.)
I found Ballard (47 yrs.) and Emma (35 yrs.) in the 1910 census in Albemarle County, VA (E.D. 10, sheet 11, lines 77-84).It indicates that she was born in Virginia, and had 5 children.All 5 are listed in the census: Bertha S Mawyer (7 mos), Ida B Simpson (16 yrs), Elmer B Simpson (13 yrs), Hubert S Simpson (11 yrs), Ernie M Simpson (8 yrs).Emma and Ballard had been married for 1 year.Ballard's daughter, Minnie (Sylvia's mother, 15 yrs) was there too.She is listed as Simpson, but the relationship is listed as daughter of Ballard.
According to Sylvia, Ballard and Emma moved to Highpoint, NC, while he was working for the railroad.He is buried there.I'm not sure about Emma's final resting place.
Obviously, Simpson was Emma's married name.I have not been able to find any more about her so far.