As more plantations were built the slave population would migrate. Please read Author Henry Wiencek's explanation of the general migration pattern for the Hairston Family
"I believe that the Berry Hill slaves were owned by PWH's grandmother Ruth Hairston and the Oak Hill slaves were owned by PWH's father Samuel Hairston, so they would probably not turn up on the Cooleemee list, but I'm not sure. Possibly Ruth or Samuel sold or gave some of their slaves to PWH at some point, but I don't know. Some of the Berry Hill slaves were taken to Mississippi by Ruth's husband, Robert, in the 1830s. Some of those people were auctioned after Robert's death. Also, many of the slaves Ruth Hairston controlled at Berry Hill and other places were legally owned by the estate of her father, "Saura Town" Peter Hairston, because Ruth refused to probate his will because she did not want to take legal title to those slaves because she did not want her husband Robert to get ownership of them."