William Cavendish (1783-1812)

William Cavendish (10 January 1783 – 15 January 1812) was an English politician, the son of Lord George Cavendish, later Earl of Burlington.

He married Louisa O'Callaghan (d. 1863), daughter of Cornelius O'Callaghan, 1st Baron Lismore, on 18 July 1807. They had four children: (Upon William's accession as Duke of Devonshire in 1858, his siblings were granted precedence of the children of a duke by Royal Warrant.)
 * Lady Fanny Cavendish (d. 30 December 1885), married Frederick John Howard and had issue
 * William Cavendish, 7th Duke of Devonshire (1808–1891)
 * Lord George Henry Cavendish (19 August 1810 – 23 September 1880)
 * Lord Richard Cavendish (3 July 1812 – 19 November 1873)

William predeceased his father in 1812; his father was subsequently created Earl of Burlington in 1831, a title which passed to William's son William, who also succeeded as Duke of Devonshire.