At
Friedenstein Castle in Gotha on 7 June 1696, he married his first cousin,
Magdalena Augusta of Anhalt-Zerbst. They had nineteen children of which only nine survived into adulthood: • Sophie (b. Gotha, 30 May 1697 – d. of smallpox, Gotha, 29 November 1703), died in early childhood. •
Frederick III, Duke of Saxe-Gotha-Altenburg (b. Gotha, 14 April 1699 – d. Gotha, 10 March 1772). • Stillborn son (Gotha, 22 April 1700). •
Wilhelm (b. Gotha, 12 March 1701 – d. Gräfentonna, 31 May 1771), married on 8 November 1742 to Anna of Holstein-Gottorp. Their marriage was childless. • Karl Frederick (b. Gotha, 20 September 1702 – d. [of smallpox?] Gotha, 21 November 1703), died in early childhood. • Stillborn daughter (b. and d. Gotha, 8 May 1703). •
Johann August (b. Gotha, 17 February 1704 – d. Stadtroda, 8 May 1767). • Christian (b. Gotha, 27 February 1705 – d. of smallpox, Gotha, 5 March 1705), died in infancy. • Christian Wilhelm (b. Gotha, 28 May 1706 – d. Stadtroda, 19 July 1748), married on 27 May 1743 to Luise Reuss of Schleiz. Their marriage was childless. • Ludwig Ernst (b. Gotha, 28 December 1707 – d. Gotha, 13 August 1763), died unmarried and without issue. • Emanuel (b. Gotha, 5 April 1709 – d. Gotha, 10 October 1710), died in early childhood. • Moritz (b. Altenburg, 11 May 1711 – d. Altenburg, 3 September 1777), never married and died without issue. • Sophie (b. Altenburg, 23 August 1712 – d. Altenburg, 12 November 1712), died in infancy. • Karl (b. Gotha, 17 April 1714 – d. Gotha, 10 July 1715), died in early childhood. •
Fredericka (b. Gotha, 17 July 1715 – d. Langensalza, 12 May 1775), married on 27 November 1734 to
Johann Adolf II, Duke of Saxe-Weissenfels. • Stillborn son (Gotha, 30 November 1716). • Magdalena Sibylle (b. Gotha, 15 August 1718 – d. Gotha, 9 November 1718), died in infancy. •
Augusta (b. Gotha, 30 November 1719 – d. Carlton House, 8 February 1772), married on 8 May 1736 to
Frederick, Prince of Wales. They had nine children; their second child
later became King
George III of Great Britain. •
Johann Adolf (b. Gotha, 18 May 1721 – d. Friedrichstanneck, 29 April 1799). ==Ancestry==