Joseph married Elizabeth. Elizabeth died on 13 Dec 1729.
Children of Joseph and Elizabeth Underwood, the first two born at Reading, the next at Charlestown, and the others at Watertown:
i. Mary Underwood, b. 13 Jun 1673, probably d. young;
ii. Joseph Underwood, b. 30 Dec 1675, d. 29 Jan 1675/6;
iii. John Underwood, b. 6 Mar 1676/7;
iv. Elizabeth Underwood, b. 8 May 1679, d. 25 Dec 1757 at Ashford, CT, m. 1st at Reading, MA 24 May 1700 Nathaniel Cutler (b. 12 Mar 1658/9 at Reading, d. there 7 Jun 1714, son of Nathaniel & Mary Cutler), m. 2nd 24 Feb 1717/8 Theophilus Clark (b. 29 Sep 1670 at Medfield, d. 7 Oct 1737 at Ashford);
v. Joseph Underwood, b. 28 May 1681;
vi. Joshua Underwood, b. 31 Jan 1682/3, d. 1732 at Sherborn, MA, m. there 13 Jan 1707/8 Mercy Fairbanks (b. 18 Oct 1688 at Sherborn, dau. of Eliesur & Martha (Lovett) Fairbanks);
vii. Jonathan Underwood, b. ca. 1685, m. Ruth;
viii. Mary Underwood, b. 9 Feb 1687; and
ix. Hannah Underwood, bp. 13 Apr 1690, d. 23 Aug 1778 at Watertown, m. at Sherborn 1708 Daniel Richardson (b. 31 Aug 1685 at Medfield, MA, d. 16 Mar 1746/7 at Medway, MA).