Source - Burke's Peerage & Gentry

Lineage-Sir John Sinclair, 1st Bt.,yr s of Matthew Sinclair, 9th Laird of Longformacus, Co Berwick, by Elizabeth, his wife, dau of Sir John Swinton, of Swinton (see that family) (by his wife Margaret, dau of David Home, of Wedderburn), amassed a considerable fortune as a merchant in Edinburgh, and acquired Stevenson, Co Haddington, in 1624. He was made Baronet of Nova Scotia [Rob, you had mentioned him] on 18 June 1636, with remainder to his heirs male. He d c. 1649, having by his wife Marion McMath, besides younger issue, (there were other sons that we must trace) a s, JOHN dvp 1643, having m Isabel, dau of 7th Ld Boyd (see KILMARNOCK, B), afterwards wife of Sir John Grierson, of Lag (see that family), and had issue,

{That piece above is the news to me: There are children we can track down. So many clues are pointing to this line at this point that I'm going to get my researcher in Sterling to track down a complete list of descendants from this Sir John. }

1a JOHN (Sir), 2nd Bt

2a ROBERT (Sir), 3rd Bt

Sir John was s by his grandson,

Sir John Sinclair, 2nd Bt.; d unm c. 1652, and was s by his bro,

Sir Robert Sinclair, 3rd Bt., Sheriff of Haddington, a Privy Councillor and Baron of Exchequer, and representative in Parliament for Co Haddington 1689-1702. He had his lands erected into a Barony in 1663. Sir Robert m 1st 1663 Helen, dau of 17th Earl of Crawford and 1st Earl of Lindsay (see that title) and by her had issue, 2nd Anne (dsp), dau of Sir William Scott, of Ardross. He d July 1713, being s by his s,

Sir John Sinclair, 4th Bt., who represented Lanark in Parliament 1703-07; m 1698 Martha (d 15 May 1752), widow of Cromwell Lockhart, of Lee, Co Lanark, a Ld of Session, and dau of Sir John Lockhart, of Castlehill, sole heir on her brošs death, to a large estate, and by her had eight sons and five daus., of whom,

1a ROBERT (Sir), 5th Bt

2a James, assumed the surname of LOCKHART; m Charlotte, dau of James Boyle, and left three daus.

3a George LOCKHART, of Castlehill, became on of the senators of the Coll of Justice, by the title of Ld Woodhall, and dsp 5 May 1764.

Sir John d 1752, and was s by his est s,

Sir Robert Sinclair, 5th Bt.; m Sept 1733 Isabella, only dau of Col James Ker, by whom he had four sons and four daus., of whom,

1a JOHN (Sir), 6th Bt

2a James, ancestor of 10th Bt (see below).

Sir Robert d 1754, and was s by his est s,

Sir John Sinclair, 6th Bt., who s to Alexander, 9th Earl of Caithness, in Murkle, and other lands under an entail; m Mary, yst dau of of William Blair, of that Ilk (see BURKE's L.G. 1952 edn), and d 13 Feb 1789, being s by his est s,

Sir Robert Sinclair, 7th Bt., Lt-Govr of Fort St George, in Scotland; m 2 April 1789 Madeline (who m 2nd 25 Nov 1805 Charles Fyshe Palmer, and d 31 May 1847), 2nd dau of 4th Duke of Gordon (see RICHMOND and GORDON, D), and by her had issue. Sir Robert d 4 Aug 1795, leaving an only s,

Sir John Gordon Sinclair, 8th Bt., a distinguished seaman, who was sixty-three years in the Roy Navy, served when a mere youth in the Victory flagship under Ld Nelson. Whose own gallant conduct while commanding the Redwing in the Mediterranean, at Morjean and Cassis, was offically commended and won much public approbation. He became a Capt 1814, and an Adml. 1861, He was b 31 July 1790; m 15 June 1812 Anne (d 23 Sept 1857), only dau of Adml. Hon Michael De Courcy, and niece of 26th Baron Kingsale (see BURKEšs PEERAGE & BARONETAGE 1999 edn), and had issue, with three other daus. (d unm),

1a ROBERT CHARLES (Sir), 9th Bt

2a John Michael De Courcy, Capt RA; b 22 Nov 1823; d Secunderabad 15 June 1862.

3a Gordon Cornwallis, Lt RN; b 13 Aug 1835; d 21 March 1866.

1a Madalina; m 15 Oct 1839 Capt Hon Dudley Pelham, RN He d 13 April 1851. and d 11 Nov 1910, leaving issue (see BURKEšs PEERAGE & BARONETAGE 1999 edn, YARBOROUGH, E). The Hon Mrs. Dudley W. Pelham s to the Sinclair estates on the death of her bro 1899, and assumed the additional name of SINCLAIR.

2a Susan Hay; m 12 June 1867 Gen Wilbraham Oates Lennox, VC, KCB, who d 7 Feb 1897, leaving issue. Lady Lennox s to the Sinclair estates on the death of her sis 1910, and assumed by deed poll the additonal surname of SINCLAIR. She d 6 April 1912, when the Sinclair estates devolved upon her elder surv s (see RICHMOND AND GORDON, D).

Adml Sir John Gordon Sinclair d 13 Nov 1863, and was s by his est s,

Sir Robert Charles Sinclair, 9th Bt., of Stevenson, Co Haddington and Murkie, Co Caithness, DL and JP, Capt 38th Regt, Hon Col 1st Caithness Art. Vol, Vol Officersš decoration; b 25 Aug 1820; m 1st 1851 Charlotte Anne (d 7 July 1874), dau of Lt John Coote, 71st Regt, and m 2nd 5 Dec 1876 Louisa (d 29 Jan 1931), est dau of Roderick Hugonin, of Kimmylles House, Inverness, and dsp 5 May 1899, when he was s by his kinsman.

Lineage-(of 10th Baronet)-JAMES SINCLAIR, afterwards LOCKHART, of Castlehill, Co Lanark, yr s of Sir Robert Sinclair, 5th Bt (see above), s to Castlehill 1764 on the death of his paternal uncle, George Lockhart, Ld Woodhall (see above), and assumed the surname of Lockhart, He m 1773 Mary Aemelia, dau of Walter Nisbet, of Nevis, and had a s and heir,