Census data for 1850, 1860, and 1870 suggest that Robert J Blevins is brother to William Gatewood Blevins.
Notations on findagrave for
"William Elbert Blevins" state that "The father, Robert J Blevins, left his family about 1888 and disappeared into Texas, it is assumed."
Margaret Ann "Maggie" KUHN Blevins (findagrave id#85271241) state "Spouse Robert J Blevins, B 1845 in Hawkins Co TN"
and on child Markie Blevins: father disappeared 1887, spent time in Van Alstyne TX, then in 1896 he disappeared again.
AC and Catherine Blevins have a joint headstone in Van Alstyne Cemetery, with dates of death as 1887 & 1888. Son of AC & Catherine, also named AC Blevins is in Texas Census, son JOHN N is also buried in Van Alstyne Cemetery.