He married
Charlotte Boyle Walsingham in London on 3/4 August 1791. Together they lived at Boyle Farm,
Thames Ditton. In 1806, the abeyance of the
Barony de Ros, the premier barony in the Peerage of England, was terminated in his wife's favor and she succeeded as 20th Baroness de Ros. The family then took the surname FitzGerald-de Ros. The couple had 13 children in 21 years, of which nine survived to adulthood: •
Henry William FitzGerald-de Ros, 21st Baron de Ros (1792–1839) •
Lt. Col. Arthur John Hill FitzGerald-de Ros (21 December 1793 – 23 February 1826) • Emily FitzGerald (1795 – unknown), died in childhood •
General William Lennox Lascelles FitzGerald-de Ros, 22nd Baron de Ros (1797–1874) • Hon. Edmund Emilius Boyle FitzGerald-de Ros (4 May 1799 – 12 September 1810), died in childhood • Hon. Charlotte FitzGerald-de Ros (1801–1813), died in childhood • Hon. Henrietta Mabel FitzGerald-de Ros (1802 – 22 December 1879), married on 24 October 1828 John Broadhurst of Foston Hall (d. 1861) •
RAdm. Hon. John Frederick FitzGerald-de Ros (6 March 1804 – 19 June 1861) • Augustus FitzGerald-de Ros (b. 1805), died in childhood • Hon. Olivia Cecilia FitzGerald-de Ros (11 January 1807 – 21 April 1885), married on 22/23 October 1833
Henry Wellesley, 1st Earl Cowley • Hon. Geraldine FitzGerald-de Ros (1809 – 28 September 1881), married on 25 November 1830 The Rev. Frederic Pare • Hon. Cecilia FitzGerald-de Ros (1811 – 6 October 1869), married on 10 December 1835 The Hon.
John Boyle (1803–1874), son of
Edmund Boyle, 8th Earl of Cork and had issue • Hon. Jane FitzGerald-de Ros (1813–1885), married Christopher Hamilton, and had issue ==References==