He married the Honourable Mabel Theresa Duncombe (1877–1913) the daughter of
William Duncombe, Viscount Helmsley. They had four daughters: • Marion Frances Theresa Beckett (8 Nov 1896 – 2 Feb 1972) married Vice-Admiral Henry Jack Egerton, son of Charles Augustus Egerton and Lady Mabel Annie Brassey, on 16 October 1919 • Cynthia Maud Beckett (15 Dec 1900 – 25 Dec 1969) married Captain John Arthur Davison, son of Major Arthur Pearson Davison, on 10 November 1919. Divorced 1928. She married German author and
BT-correspondent Kurt Hermann Paul Otto Valerio Baron von Stutterheim (1888-1978), son of
Richard Karl Ludwig Baron von Stutterheim, on 10 July 1929. Divorced in 1952. •
Beatrice Helen Beckett (26 Jul 1905 – 29 Jun 1957) – married
Anthony Eden in 1923. Divorced in 1950. • Ann Prunella Beckett (16 Sep 1907 – 17 Mar 2001) married Lt.-Col. Harry Rumbold Bathurst Norman, son of Reverend Harry Bathurst Norman, on 15 April 1936. Secondly he married Lady Marjorie Blanche Eva Greville, daughter of
Francis Richard Charles Guy Greville, 5th Earl of Warwick and Frances Evelyn Maynard, on 1 November 1917. Lady Greville was the widow of
Charles Duncombe, 2nd Earl of Feversham, his first wife's brother. This marriage produced one son: • Sir Martyn Gervase Beckett, 2nd Bt (6 Nov 1918 – 5 Aug 2001) The publisher Sir
Rupert Hart-Davis (1907-1999) was legally the son of stockbroker Richard Hart-Davis and his wife Sybil, daughter of the surgeon Sir
Alfred Cooper; by the time of his conception, the Hart-Davises were estranged, and Sybil had numerous lovers at that period. Hart-Davis considered Beckett to be the most likely candidate for his natural father. Beckett was created a
baronet in the
1921 Birthday Honours, as Sir Gervase Beckett, 1st Baronet Beckett, of Kirkdale Manor in the County of
Yorkshire. ==Footnotes==