Question: Who is Lord Herbert Montagu Douglas Scott's maternal grandfather?

Knowledge 1: Lord Herbert Montagu Douglas Scott
Lieutenant-Colonel Lord Herbert AndrewMontagu Douglas Scott, CMG, DSO (30 November 1872 – 17 June 1944) was the fifth child born to William Henry Walter Montagu Douglas Scott, 6th Duke of Buccleuch & 8th Duke of Queensberry and Lady Louisa Jane Hamilton.Lord Herbert Andrew was a great-grandfather to Sarah, Duchess of York, and a maternal second great-grandfather (great-great-grandfather) to Princess Beatrice of York and Princess Eugenie of York.He was also a paternal uncle of Princess Alice, Duchess of Gloucester, previously Lady Alice Montagu Douglas Scott, and thereby a maternal granduncle to Prince William of Gloucester and Prince Richard, Duke of Gloucester. [SEP] Knowledge 2: Louisa Montagu Douglas Scott, Duchess of Buccleuch
Louisa Jane Montagu Douglas Scott, Duchess of Buccleuch and Queensberry (26 August 1836 – 16 March 1912) was the daughter of James Hamilton, 1st Duke of Abercorn.In 1884, she became the Duchess of Buccleuch and Duchess of Queensberry, the wife of William Henry Walter Montagu Douglas Scott, 6th Duke of Buccleuch & 8th Duke of Queensberry.She was the paternal grandmother of Princess Alice, Duchess of Gloucester and of Marian Louisa, Lady Elmhirst, as well as the maternal great-grandmother of Prince William of Gloucester, Prince Richard, Duke of Gloucester and great-great-grandmother of Sarah, Duchess of York.
Knowledge 1: Lord Herbert Montagu Douglas Scott
Lieutenant-Colonel Lord Herbert AndrewMontagu Douglas Scott, CMG, DSO (30 November 1872 – 17 June 1944) was the fifth child born to William Henry Walter Montagu Douglas Scott, 6th Duke of Buccleuch & 8th Duke of Queensberry and Lady Louisa Jane Hamilton.Lord Herbert Andrew was a great-grandfather to Sarah, Duchess of York, and a maternal second great-grandfather (great-great-grandfather) to Princess Beatrice of York and Princess Eugenie of York.He was also a paternal uncle of Princess Alice, Duchess of Gloucester, previously Lady Alice Montagu Douglas Scott, and thereby a maternal granduncle to Prince William of Gloucester and Prince Richard, Duke of Gloucester. [SEP] Knowledge 2: Lord George Scott
Lord George William Montagu Douglas Scott,( 31 August 1866 – 23 February 1947) was a Scottish cricketer and soldier.He was the brother of John Montagu Douglas Scott, 7th Duke of Buccleuch and the son of William Montagu Douglas Scott, 6th Duke of Buccleuch.Princess Alice, Duchess of Gloucester was his niece.Scott was born in Bowhill, Selkirkshire, the third son of William Montagu Douglas Scott, 6th Duke of Buccleuch.He was educated at Eton and Christ Church, Oxford.He played first- class cricket for various teams including Middlesex, Marylebone Cricket Club( MCC) and Oxford University from 1884 to 1905.He represented the Gentlemen in the Gentlemen v Players series.He was also Master of the Buccleuch Hunt.Scott was commissioned a second lieutenant in the 10th Hussars on 27 March 1889, was promoted to the rank of lieutenant on 11 June 1890, and to captain on 25 June 1897.He served in the Second Boer War, and left the regular army in August 1902.He later commanded the 2/1st Lothians and Border Horse, a Yeomanry( later Territorial Army) regiment, through World War I until January 1919 when he retired.He was appointed OBE in the 1919 Birthday Honours.He was a Deputy Lieutenant of Roxburghshire.In 1903, Scott married Lady Elizabeth Manners( died 1924), the youngest daughter of the John Manners, 7th Duke of Rutland.Together they had two sons and three daughters.His eldest daughter, Georgina Mary Scott, married Raymond O' Neill, 4th Baron O'Neill in 1963.He died in Melrose, Scottish Borders.
Knowledge 1: Lord Herbert Montagu Douglas Scott
Lieutenant-Colonel Lord Herbert AndrewMontagu Douglas Scott, CMG, DSO (30 November 1872 – 17 June 1944) was the fifth child born to William Henry Walter Montagu Douglas Scott, 6th Duke of Buccleuch & 8th Duke of Queensberry and Lady Louisa Jane Hamilton.Lord Herbert Andrew was a great-grandfather to Sarah, Duchess of York, and a maternal second great-grandfather (great-great-grandfather) to Princess Beatrice of York and Princess Eugenie of York.He was also a paternal uncle of Princess Alice, Duchess of Gloucester, previously Lady Alice Montagu Douglas Scott, and thereby a maternal granduncle to Prince William of Gloucester and Prince Richard, Duke of Gloucester. [SEP] Knowledge 2: Andrew Montagu Douglas Scott
Brigadier Claud Andrew Montagu Douglas Scott, DSO( 13 July 1906 – 24 January 1971) was the first child and only son born to Lieutenant Colonel Lord Herbert Andrew Montagu Douglas Scott and Marie Josephine Edwards.He was a grandson of Sir William Henry Walter Montagu Douglas Scott, 6th Duke of Buccleuch& 8th Duke of Queensberry and Lady Louisa Jane Hamilton, and a paternal first cousin to Lady Alice, Duchess of Gloucester, later known as Princess Alice, Duchess of Gloucester.He was a maternal first cousin once removed to Prince William of Gloucester and Prince Richard, Duke of Gloucester, a paternal great- uncle to Sarah, Duchess of York, and a maternal second great- uncle to Princesses Beatrice and Eugenie of York.

Answer: James Hamilton