I have marriage record for John Parker who married Nancy Collins (father Jacob Collins)in 1807. Their daughter Abigail Parker married William Farmer. I have that cert also. Abigail's daughter Nancy farmer married Thomas James Eli. Nancy Parker(61) on the 1850 census was living with her daughter Abigail. There is a John C Parker on the 1850 census in Christian County with the wife you mentioned.
Their son A R Parker died in Christian County and i have that death certificate. There is some confusion here I think.