Your original message states Tracy Gulsby lived in Franklin county 1930 census. It was actually the 1920 census and "Ada" was born in Kentucky in 1896. My best guess is they married 1916-1917.
You can request a Genealogical Copy of a marriage record fo $2.00 from Franklin County. www.franklincountyil.gov
Scroll down to Application for Marriage Certificate and open the pdf file to print the form if you want to see if they can find it.
I can not explain why Mary Goolsby, or another person, thought that her father was Nathan Goolsby. She was about 10 when her father Tracy died.