Jacob married Hester Paine. Hester died on 10 May 1760.
Children of Jacob and Hester (Paine) Cornwell, born at Flushing:
i. Jacob Cornwell, b. 10 Jun 1700, d. 31 Aug 1769, m. 1 Jun 1721 Hannah Hicks (d. 4 Sep 1770);
ii. Daniel Cornwell, b. 1 Oct 1702, m. Mary Vail (d. 12 Jul 1786);
iii. Mary Cornwell, b. 30 Sep 1704;
iv. Elias Cornwell, 10 Nov 1706;
v. Richard Cornwell, b. 3 Sep 1708, d. 13 Sep 1794 at Beekman, Dutchess Co., NY, m. at Hempstead, NY, 31 Dec 1731 his first cousin Elizabeth Cornell (dau. of Thomas and Charity Doughty (Hicks) Cornell);
vi. Samuel Cornwell, b. 4 May 1710;
vii. Sarah Cornwell, b. 11 Aug 1711;
viii. Elijah Cornwell, b. & d. 14 Jul 1713;
ix. Elisha Cornwell, twin, b. & d. 13 Jul 1713;
x. Esther Cornwell, b. 3 Apr 1716; and
xi. Hannah Cornwell, b. 4 Jun 1719.