In 1814 Joseph freed at least one of his slaves, named George Freeman.
The certificate said that he believed all men should be free; however, he did still keep some slaves which were sold after his death.
http://www.stupakgen.net/Genealogy/Spencer/00160_spen.htm (broken link?)
--------------------
George was a mulatto and a freed slave.
He and Clarissa Centers did not marry but had 10 children together.
Clarissa had a son Franklin Centers from a previous relationship.
There is a son Hiram attached at Findagrave who cannot be a child of Clarissa if the dates are correct.
Research ongoing to bring together the family group.