Robert Carnegie, 13th Earl of Northesk
Robert Andrew Carnegie, 13th Earl of Northesk (24 June 1926 – 26 January 1994) was a British landowner, farmer and hereditary peer.
He was the son of John Carnegie, 12th Earl of Northesk and Dorothy May Campion.
Carnegie was educated at Pangbourne Nautical College and Tabor Academy, Massachusetts.
He served in the Royal Navy 1942–45.
He was an amateur racing driver (racing as "Robin Carnegie") and raced at Le Mans and in the Mille Miglia.
In the 1970s he moved to the Isle of Man where he bred Charolais cattle and exported them throughout the world.
On 20 July 1949, he married Jean Margaret MacRae, daughter of Captain John Duncan George MacRae and Lady Phyllis Hervey, daughter of the 4th Marquess of Bristol.
They had four children:
David Carnegie, 5th Earl of Northesk
David Carnegie, 5th Earl of Northesk( 11 June 1701 – 24 June 1741) was the son of David Carnegie, 4th Earl of Northesk and Lady Margaret Wemyss.
He died at the age of 40, unmarried.
He had, by Isabel Rarity, a son, Sylvester who was born on 16 January 1732, and married Margaret Peter on 9 June 1755.
John Carnegie, 12th Earl of Northesk
John Douglas Carnegie, 12th Earl of Northesk (16 February 1895 – 22 July 1975) inherited the earldom in 1963.
Carnegie was born the son of Lt.-Col.
Hon.
Douglas Carnegie and Margaret Jean Johnstone-Douglas on 16 February 1895.
He was educated at Gresham's School, Holt and King’s College, Cambridge, and served in World War I of 1914–1918 (mentioned in despatches),
Captain (temporary Major), 95th (Hants Yeomanry) Brigade, Royal Field Artillery (TA).
Carnegie married Dorothy May Campion, daughter of Colonel Sir William Robert Campion and Katherine Mary Byron, on 20 July 1920.
They had four children:
In 1963, Carnegie inherited the earldom from his first cousin David Carnegie, 11th Earl of Northesk, who had died childless.
Sidney Herbert, 16th Earl of Pembroke
Sidney Herbert, 16th Earl of Pembroke, 13th Earl of Montgomery( 9 January 1906 – 16 March 1969) was a British peer.
Charles Carnegie, 4th Earl of Southesk
Charles Carnegie, 4th Earl of Southesk( 1661–1699) was a Scottish nobleman.
He inherited the earldom from Robert Carnegie, 3rd Earl of Southesk.
Robert Carnegie, 3rd Earl of Southesk
Robert Carnegie, 3rd Earl of Southesk( b. before 1649 – 1688) was a Scottish nobleman.
George Carnegie, 6th Earl of Northesk
Admiral George Carnegie, 6th Earl of Northesk( 1716–1792) was born the son of David Carnegie, 4th Earl of Northesk and Lady Margaret Wemyss on 2 August 1716.
He died on 20 January 1792 at age 75.
He married Anne Melville, daughter of Alexander Melville, 5th Earl of Leven and Elizabeth Monypenny, on 30 April 1748 and had six children:
David Carnegie, 2nd Earl of Northesk
David Carnegie, 2nd Earl of Northesk was born the son of John Carnegie, 1st Earl of Northesk and Magdalen Haliburton before 1627.
He died on 12 December 1679.
He married Lady Jean Maule, daughter of Patrick Maule, 1st Earl of Panmure, on 19 October 1637 and had seven children:
By his third son, Patrick, he is the seventh great- grandfather of the 15th Earl of Northesk.
David Carnegie, 3rd Earl of Northesk
David Carnegie, 3rd Earl of Northesk( 1643 – 1688) was born the son of David Carnegie, 2nd Earl of Northesk and Lady Jean Maule, daughter of Patrick Maule, 1st Earl of Panmure in November 1643.
He married Elizabeth Lindsay, daughter of John Lindsay, 17th Earl of Crawford and Lady Margaret Hamilton, on 2 September 1669 and had two children:
William Carnegie, 7th Earl of Northesk
Admiral William Carnegie, 7th Earl of Northesk GCB( 19 April 1758 – 28 May 1831) was born at Bruntsfield in Edinburgh to Admiral George Carnegie, 6th Earl of Northesk and Anne Melville.

Question: Who is the paternal grandfather of Robert Carnegie, 13Th Earl Of Northesk?
Answer: Douglas Carnegie