Onez was one of the 33 slaves purchased from the Bartholomew Dandridge Estate in 1788. On 24 April of that year, GW had Burwell Bassett, Jr., purchase 33 slaves and some stock from the estate of Bartholomew Dandridge, Sr. While the acquired slaves and stock belonged to GW, they were left at Pamocra, New Kent County, Va., with Dandridge's widow, Mary Burbidge Dandridge. In his last will and testament, GW released the Bartholomew Dandridge Estate from debt and declared that the slaves should remain in the possession of Mary Dandridge "during her natural life." Upon Mary's death, GW directed that those slaves who were "forty years old & upwards," be freed, while the slaves over the age of sixteen and under the age of forty would serve seven years. GW further directed that those slaves under the age of sixteen "shall serve until they are twenty five years of age, and then be free." [George Washington’s Last Will and Testament: Rotunda | Founders Online | Print (Retirement Series, Volume 4, pages 484 – 85)].