I looked at the 1920 Campbell Co. census (on-line) and found the following:
Mason Bridge Rd., Sandtown District
Family #117 is John A. Brock, age 70; wife Elizabeth, 61, and son A????s, 14. The next family (#118) is a Swann family who were black.
Swann, Wilson(?) 39
A???? L. 14 (female)
The handwriting is very difficult to read, so I may have some of the info wrong.
John A. Brock was the s/o of John Brock and Ginsey Thomas. John Brock and Henry Brock were the only two Brock’s on the 1830 Campbell Co. census and were probably brothers from SC.
If these are the Swann’s you are seeking, let me know. I have much info about the Brock’s (I am descended from Henry), but nothing about the Swann’s. I would be interested in finding out if the two families were related. It might help solve a mystery involving Europha Brock. She is identified on the 1870 census as black, living next to Joel Brock (s/o Henry). She left a will (in which she is classified as “Colored”) which mentions several of her children and was witnessed by Joel Brock and Thomas Brock (both sons of Henry). Joel and Thomas were listed as executors. It seems likely that Europha was a former slave whose children were fathered by a Brock male (most likely Henry but possibly John or one of their sons).