On 2 Jun 1757 when Thomas was 22, he married Mary in Plymouth, MA.

Children of Thomas and Mary Foster, the first five at Marshfield:
    i. Thomas Foster, b. 16 Apr 1758, d. 29 May 1759;
    ii. John Foster, b. 3 Feb 1760, d. 5 Oct 1760;
    iii. Peter Foster, b. 16 Jul 1761, d 2 Jun1772;
    iv. Nathaniel Foster, b. 15 Jun 1763, d. 2 Jun 1772;
    v. Mary Foster, b. 21 Dec 1765, m. Levi Tihkham
    vi. Mercy Thatcher Foster, b. 13 Aug 1768, d. 24 Mar 1773;
    vii. Susanna Foster, b. 8 Jun 1771; and
    viii. Rebecca Foster, b. 24 Sep 1773.

On 27 Mar 1760 Deborah married Anthony Waterman (42305) , son of Thomas Waterman (30613) (29 Apr 1710-27 Aug 1774) & Abigail Thomas (22466) (5 Apr 1710-5 Jan 1796), in Marshfield, MA. Born on 3 Dec 1736 in Marshfield, MA. Anthony was baptized in Marshfield, MA, on 19 Dec 1736. Anthony died in Scituate, MA, on 24 Sep 1799; he was 62.52 Buried in Church Hill Cemetery, Norwell.