Samuel Wallis married Lydia Hollingsworth in Philadelphia on March 1, 1770. They settled at Muncy Farms soon after the marriage and continued to farm while Wallis continued to expand his land holdings. Wallis was forced to flee Muncy Farms during the "Big Runaway". During the American Revolutionary War, settlements throughout the Susquehanna valley were attacked by Loyalists and Native Americans allied with the British. After the Wyoming Valley battle and massacre in the summer of 1778 (near what is now Wilkes-Barre) and smaller local attacks, the Big Runaway occurred throughout the West Branch Susquehanna valley. Settlers fled feared and actual attacks by the British and their allies. Homes and fields were abandoned, with livestock driven along and a few possessions floated on rafts on the river east to Muncy, then further south to Sunbury. The abandoned property was burnt by the attackers. Some settlers soon returned, only to flee again in the summer of 1779 in the "Little Runaway". Sullivan's Expedition helped stabilize the area and encouraged resettlement, which continued after the war. Wallis returned as soon as it was safe and continued to farm. He also built a gristmill along Carpenter's Run. The construction of this mill was entrusted to Colonel Henry Antes of Nippenose Township. Antes was the operator of the most successful mill in the area, along Antes Creek.