In 1850, Pontotoc County, Mississippi, living near Vance Abernathy was a S Abernathy, age 83, and his wife, Ruth, age 71. The ages are just right for this to be your David W Abernathy and Ruth. The initial appears to be an S, but I guess it could be a D. I had thought this might be Smith Abernathy. Family tradition says that Samuel Vance and Eleanor were first cousins, which would be the case if Samuel V were a son of Smith, but I havenever seen the name David Wilson Abernathy before. Do you recall where you found that DW and SV were father and son?