John Churchill (b. 26 May 1650 – d. 16 Jun 1722) married Sarah Jennings (b. 5 Jun 1660 – d. 18 Oct 1744), daughter of Richard Jennings, MP for St Albans. They had seven children:

1. Harriet (b. Oct 1679 – d. Oct 1679)
2. Henrietta (b. 19 Jul 1681 – d. 24 Oct 1733) m. Francis Godolphin, 2^nd Earl of Godolphin, son of Sidney Godolphin, 1^st Earl of Godolphin
3. Anne (b. 27 Feb 1684 – d. 15 Apr 1716) m. Charles Spencer, 3^rd Earl of Sunderland, son of Charles Spencer, 2^nd Earl of Sunderland
4. John, Marquess of Blandford (b. 12 Jan 1686 – d. 20 Feb 1703)
5. Elizabeth (b. 15 Mar 1687 – d. 22 Mar 1714) m. Scroop Egerton, 1^st Duke of Bridgewater, son of John Egerton, 3^rd Earl of Bridgewater
6. Mary (b. 15 Jul 1689 – d. 14 May 1751) m. John Montagu, 2^nd Duke of Montagu, son of Ralph Montagu, 1^st Duke of Montagu
7. Charles (b. 19 Aug 1690 – d. 22 May 1692)