On 7 Jul 1748 when Israel was 26, he married Anna Lawrence (46792) , daughter of William Lawrence (11 Aug 1697-19 May 1764) & Susanna Prescott (28333) (31 Dec 1691-10 Sep 1771), in Groton, MA. Born 24 Jan 1727/8 in Groton, MA. Anna died in Townsend, MA on 5 Apr 1791.

Israel and Anna were first cousins; their mothers were sisters.