William Faithfull was born 1774 in Hampshire, England, United Kingdom and died 1847 Richmond, New South Wales, Australia of unspecified causes. He married Susannah Pitt (1774-1820) 21 November 1804 in Parramatta, New South Wales, Australia. He married Margaret Thompson (1789-1842) 27 November 1821 in Liverpool, New South Wales, Australia. He married Maria Bell (1795-1859) 13 June 1843 in Richmond, New South Wales, Australia.
He arrived in New South Wales on 14 February 1792 on the Pitt as a private in the NSW Corps (102nd regiment).
Children
| Name | Birth | Death | Joined with |
| William Pitt Faithfull (1806-1896) | 11 October 1806 Richmond, New South Wales, Australia | 24 April 1896 Quialigo, Goulburn, New South Wales, Australia | Margaret Considine Mary Deane (1804-1889) |
| Robert Faithfull (1808-1812) | 2 July 1808 Richmond, New South Wales, Australia | 24 August 1812 Richmond, New South Wales, Australia | |
| Alice George Faithfull (1811-1888) | 8 January 1811 Richmond, New South Wales, Australia | 27 January 1888 Goulburn, New South Wales, Australia | Andrew Gibson (1796-1840) |
| George Faithfull (1814-1855) | 5 January 1814 Canterbury, New South Wales, Australia | 22 October 1855 Wangaratta, Victoria, Australia | Jane McKenzie (1821-1882) |
| Name | Birth | Death | Joined with |
| Helen Eliza Faithfull (1824-1847) | 1824 Richmond, New South Wales, Australia | 24 April 1847 Sydney, New South Wales, Australia | Thomas Matcham Pitt Wilshire (1821-1852) |
| James Robert Faithfull (1825-1827) | 25 August 1825 Richmond, New South Wales, Australia | 1827 Richmond, New South Wales, Australia | |