On 13 Sep 1770 when Gershom was 25, he married Jemima Farrow (39212) , daughter of Thomas Farrow (19835) (10 Apr 1721-) & Jemima Damon (37549) (9 Mar 1723-), in Scituate, MA.52 Born ca 1746 in Scituate, MA. Jemima was baptized in the Second Church of Scituate, on 4 May 1746.52

Gershom and Jemima were first cousins; their fathers were brothers.