The Fosters were married on November 14, 1807 in Chambersburg, Pennsylvania. William Barclay Foster was a leader on the western frontier of Pennsylvania. He had settled near Pittsburgh. The Fosters had several children: Charlotte Susanna (1809), Ann Eliza (1812), Henry Baldwin (1816), Henrietta Angelica (1818), Dunning McNair (1821), Morrison (1823), and Stephen Collins (1826). A son was born in 1829, but died in 1830. 