He had nine sons, one of them died at a young age. The eldest son, Charles, the 3rd viscount (1700–1764), was called to the House of Lords in 1723. The second son, Thomas Townshend (1701–1780), was member of parliament for the University of Cambridge from 1727 to 1774; his only son, Thomas Townshend (1733–1800), who was created Baron Sydney in 1783 and Viscount Sydney in 1789, was a secretary of state and Leader of the House of Commons from July 1782 to April 1783, and from December 1783 to June 1789 again a secretary of state, Sydney in New South Wales being named after him; his grandson, John Robert Townshend (1805–1890), the 3rd viscount, was created Earl Sydney in 1874, the titles becoming extinct at his death. Charles Townshend's eldest son by his second wife was George Townshend (1715–1769), who after serving for many years in the navy, became an admiral in 1765. The younger son Edward (1719–1765) became Dean of Norwich