In the 1880 census there are more Lampkins living adjacent (I suspect since they appear one after another on the census sheet) to William and Nancy Jones.
There is a Charles and Hannah Lampkin (#1986, both born in NC, and aged 84 and 77). Could they be Nancy's parents.
Also there is a John Lampkin household (#1987) nearby (age 41). He could be Nancy's brother. The birthplace of the parents match up.
What do you think? Do you have more information about Nancy's parent's and their migration from NC?