Hi,

I am not sure if this is your ancestor, that I found in Ben Hill Co. Georgia. They were found in the 1920 census.

Harper, Oscar- head- male- black- age 40
----- Edna- wife- female- black- age 37
----- Alma- daughter- female- black- age 10

I did find a Oscar Harper who died in 1920 in Ben Hill County Ga. but I am not sure if this is your Harper. I couldn't find them in any other census, maybe someone else could find more.

James