Edith Lilian Hamilton1 
Her married name became Sinclair.
Children of Edith Lilian Hamilton and Norman Alexander Sinclair
- Sir Ronald Norman John Charles Udny Sinclair of Dunbeath, 8th Bt.+2 b. 30 Jun 1899, d. 19 Oct 1952
- Alexander Robert Sinclair+2 b. 26 Sep 1901, d. 1972
Norman Alexander Sinclair1 
Children of Norman Alexander Sinclair and Edith Lilian Hamilton
- Sir Ronald Norman John Charles Udny Sinclair of Dunbeath, 8th Bt.+2 b. 30 Jun 1899, d. 19 Oct 1952
- Alexander Robert Sinclair+2 b. 26 Sep 1901, d. 1972
Helen Violet Hamilton1
Helen Violet Hamilton usually went by her middle name of Violet. Her married name became Forman.
- [S37] BP2003 volume 1, page 330. See link for full details for this source. Hereinafter cited as. [S37]
Joseph Forman1
- [S37] BP2003 volume 1, page 330. See link for full details for this source. Hereinafter cited as. [S37]
Lt.-Col. Alexander Young Sinclair 
He gained the rank of Lieutenant-Colonel in the Bombay Army.1
Children of Lt.-Col. Alexander Young Sinclair and Margaret Crichton Alston
- Margaret Sinclair+2 d. 2 Jul 1932
- Sir John Rose George Sinclair of Dunbeath, 7th Bt.2 b. 10 Aug 1864, d. 3 Nov 1926
- Norman Alexander Sinclair+1 b. 29 Jul 1869, d. 11 May 1904
Margaret Crichton Alston 
Her married name became Sinclair.
Children of Margaret Crichton Alston and Lt.-Col. Alexander Young Sinclair
- Margaret Sinclair+3 d. 2 Jul 1932
- Sir John Rose George Sinclair of Dunbeath, 7th Bt.3 b. 10 Aug 1864, d. 3 Nov 1926
- Norman Alexander Sinclair+2 b. 29 Jul 1869, d. 11 May 1904
Sir John Sinclair of Barrock, 6th Bt.1 
He succeeded as the 6th Baronet Sinclair, of Dunbeath, co. Caithness [N.S., 1704] on 1 October 1842.1
Children of Sir John Sinclair of Barrock, 6th Bt. and Margaret Learmonth
- Captain John Sinclair2 b. 2 May 1822, d. 5 Apr 1858
- Lt.-Col. Alexander Young Sinclair+ b. 16 Feb 1824, d. 3 Feb 1871
- Captain George Sinclair+3 b. 29 Jan 1826, d. 23 Mar 1871
- Grace Elizabeth Sinclair2 b. c 1832, d. 19 Aug 1849
- [S37] BP2003 volume 3, page 3631. See link for full details for this source. Hereinafter cited as. [S37]
- [S363] Fiona Sinclair, “Sinclairs of Barrock,” e-mail message to unknown recipient. Hereinafter cited as “Sinclairs of Barrock.”
- [S34] BP1970 page 2096. See link for full details for this source. Hereinafter cited as. [S34]
Margaret Learmonth1 
Her married name became Sinclair.
Children of Margaret Learmonth and Sir John Sinclair of Barrock, 6th Bt.
- Captain John Sinclair1 b. 2 May 1822, d. 5 Apr 1858
- Lt.-Col. Alexander Young Sinclair+ b. 16 Feb 1824, d. 3 Feb 1871
- Captain George Sinclair+1 b. 29 Jan 1826, d. 23 Mar 1871
- Grace Elizabeth Sinclair1 b. c 1832, d. 19 Aug 1849
John Learmonth1
Child of John Learmonth
- Margaret Learmonth+ d. 29 Nov 1879
Sir Ronald Norman John Charles Udny Sinclair of Dunbeath, 8th Bt.1 
He was educated at Wellington College, Crowthorne, Berkshire, England.1 He was educated at Royal Military College, Sandhurst, Berkshire, England.1 He gained the rank of Major in the 4th/5th Battalion, Seaforth Highlanders (Territorial Army.)1 He succeeded as the 8th Baronet Sinclair, of Dunbeath, co. Caithness [N.S., 1704] on 3 November 1926.2 He held the office of Deputy Lieutenant (D.L.) of Caithness.1 He held the office of Justice of the Peace (J.P.) for Caithness.1 He was awarded the Territorial Decoration (T.D.)1
Children of Sir Ronald Norman John Charles Udny Sinclair of Dunbeath, 8th Bt. and Reba Blair Inglis
- Sir John Rollo Norman Blair Sinclair of Dunbeath, 9th Bt.3 b. 4 Nov 1928, d. 1990
- Georgina Margaret Snowdrop Sinclair+3 b. 1932
- Susan Lilian Primrose Sinclair, Baroness Masham of Ilton+3 b. 14 Apr 1935, d. 12 Mar 2023
- [S37] BP2003 volume 3, page 3631. See link for full details for this source. Hereinafter cited as. [S37]
- [S5872] Peter Bell, “re: Mainwaring Family,” family provided evidence then verified by subsequent research and verification by BENR (101053), 14 February 2012. Hereinafter cited as “re: Mainwaring Family.”
- [S37] BP2003. [S37]