My great,great,great,great,great grandfather William witherspoon was a free slave in 1820 in Sumter,Sc. His slaveowner was name Joel L. Green. His former slave owner was named Hugh Porter of Abbeville SC. William was listed in the 1830 census records in Sumter as a free slave. He had 6 children with him but no wife. After the 1830 census, I can not find the 6 children. They were not named in the 1830 census. Do any one recognize this lost generation of freed african american slaves?