 On October 1, 1777, Congress appointed joint chaplains, William White, Duché's successor at Christ Church, and George Duffield, pastor of the Third Presbyterian Church of Philadelphia.Duché died in 1798 in Philadelphia, where he is buried in St. Peter's churchyard.His daughter, Elizabeth Sophia Duché (born on September 18, 1774, Philadelphia; died on December 11, 1808, Montréal), married Captain John Henry in 1799.