Pamela,
I did a little research on the George & Richard EVANS that were in Granville, which I feel may be the same one you are looking for. In 1860 Granville County, George was living with the Canady family along with RICH'D EVANS, age 21, DOXEY EVANS, age 17, as well as GEORGE's age was 13. This does come pretty close to the 1870 GEORGE EVANS in Halifax County, NC. Looking further back in 1850, the following household appears to have both boys living there:
1850 Wake Co.,North Carolina, Western Div, Image 120, #900/900:
RUTHA EVANS - 49 - F - B - NC
GILLY EVANS - 14 - F - B - NC
DICK EVANS - 10 - M - B - NC
DAWSON EVANS - 6 - M - B - NC
GEORGE EVANS - 3 - M - B - NC

It just may be that the GEORGE EVANS you have in 1870, was the same person who was apparently living with his brother RICHARD in 1860, and where both boys were living with their mother RUTHA EVANS in 1850 in Wake Co. The counties are so close together and there were many families who moved about to all of these locations that it should be well worth your time to check them over further.

Deloris