Following his family's master's death, young Josiah was separated from his mother, brothers, and sisters. His mother pleaded with her new owner, Isaac Riley, and Riley agreed to buy back Henson so she could at least have her youngest child with her, on the condition that he would work in the fields. Riley would not regret his decision, for Henson rose in his owners' esteem, and was eventually entrusted as the supervisor of his master's farm, located in Montgomery County, Maryland (in what is now North Bethesda).