Cormac Brendan O’Brien1
Murrough Idries O’Brien1
Zahara Grace O’Brien1
Major David Lucius O’Brien1 
He graduated with a Bachelor of Science (B.Sc.)2 He gained the rank of Major in the Royal Army Veterinary Corps.1 He was registered as a Member, Royal College of Veterinary Science (M.R.C.V.S.)2
Children of Major David Lucius O’Brien and Mary Katherine Drummond Ramsay-Steel-Maitland
- Michael David O’Brien2 b. 15 Jul 1930
- Lucia Margaret O’Brien2 b. 19 Aug 1932
Children of Major David Lucius O’Brien and Shirley Hurford
- Tasman David O’Brien+2 b. 1955
- Donough William O’Brien2 b. 1956
Albert Vincent Horatio Walpole1
- [S466] Notices, The Telegraph, London, UK, 23 August 2005. Hereinafter cited as The Telegraph.
Mary Katherine Drummond Ramsay-Steel-Maitland1 
From 7 October 1929, her married name became O’Brien.
Children of Mary Katherine Drummond Ramsay-Steel-Maitland and Major David Lucius O’Brien
- Michael David O’Brien2 b. 15 Jul 1930
- Lucia Margaret O’Brien2 b. 19 Aug 1932
Michael David O’Brien1
He lived in 2003 at Addlestead Farm, Headley, Epsom, Surrey, EnglandG.1
Lucia Margaret O’Brien1
She lived in 2003 at 84 Colehill Lane, London, EnglandG.1
Shirley Hurford1
From 1954, her married name became O’Brien.
Children of Shirley Hurford and Major David Lucius O’Brien
- Tasman David O’Brien+2 b. 1955
- Donough William O’Brien2 b. 1956
