About 1771 or as late as 1775, Whitley married Esther Fullen, also from Virginia. A few years later, he proposed that they move from Virginia to the western frontier across the Appalachian Mountains. When she approved, he organized an expedition with his brother-in-law, George Clark. The pair met another party of seven pioneers; the two parties combined and continued with their expedition. After scouting a location near a branch of the Dix River called Cedar Creek, they returned to Virginia to prepare for a permanent move west.