Question: Who is Clare Fitzroy, Countess Of Euston's paternal grandfather?

Knowledge 1: Clare FitzRoy, Countess of Euston
Clare Amabel Margaret FitzRoy, Dowager Countess of Euston (née Kerr; born 15 April 1951) is the current Lord Lieutenant of Suffolk.She is also President of the Suffolk Agricultural Association with a particular interest in local breeds the Suffolk Punch horse and the Red Poll cow.Born in Jedburgh as Lady Clare Kerr, Lady Euston is the fourth child of Peter Kerr, 12th Marquess of Lothian, and his wife Antonella (née Newland).Clare married James FitzRoy, Earl of Euston, son and heir apparent to the 11th Duke of Grafton, on 16 September 1972.He predeceased his father in 2009.Lord and Lady Euston had five children:She had previously been High Sheriff and Deputy Lieutenant of Suffolk. [SEP] Knowledge 2: Peter Kerr, 12th Marquess of Lothian
Peter Francis Walter Kerr, 12th Marquess of Lothian, (8 September 1922 – 11 October 2004) was a British peer, politician and landowner.He was the son of Captain Andrew William Kerr by his wife, Marie Kerr.Both of his parents were male-line descendants of William Kerr, 5th Marquess of Lothian.
Knowledge 1: Clare FitzRoy, Countess of Euston
Clare Amabel Margaret FitzRoy, Dowager Countess of Euston (née Kerr; born 15 April 1951) is the current Lord Lieutenant of Suffolk.She is also President of the Suffolk Agricultural Association with a particular interest in local breeds the Suffolk Punch horse and the Red Poll cow.Born in Jedburgh as Lady Clare Kerr, Lady Euston is the fourth child of Peter Kerr, 12th Marquess of Lothian, and his wife Antonella (née Newland).Clare married James FitzRoy, Earl of Euston, son and heir apparent to the 11th Duke of Grafton, on 16 September 1972.He predeceased his father in 2009.Lord and Lady Euston had five children:She had previously been High Sheriff and Deputy Lieutenant of Suffolk. [SEP] Knowledge 2: Alfred FitzRoy, 8th Duke of Grafton
Alfred William Maitland FitzRoy, 8th Duke of Grafton( 3 March 1850 – 10 January 1930), styled Lord Alfred FitzRoy between 1882 and 1912 and Earl of Euston between 1912 and 1918, was the second son of Augustus FitzRoy, 7th Duke of Grafton and his wife Anna Balfour, daughter of James Balfour( 1845) and aunt of Arthur Balfour.His elder brother and heir to the dukedom Henry James FitzRoy, Earl of Euston died in 1912, before their father's death.He married, firstly, Margaret Rose Smith( 1855–1913), on 27 April 1875 and had three children:The 8th Duke married, secondly, Susanna Mary McTaggart- Stewart( 1878 – 1961), on 8 January 1916 and had two daughters:On 15 March 1920, he was appointed a deputy lieutenant of Suffolk.The Duke died in 1930 and was succeeded by his grandson, John, Earl of Euston.
Knowledge 1: Clare FitzRoy, Countess of Euston
Clare Amabel Margaret FitzRoy, Dowager Countess of Euston (née Kerr; born 15 April 1951) is the current Lord Lieutenant of Suffolk.She is also President of the Suffolk Agricultural Association with a particular interest in local breeds the Suffolk Punch horse and the Red Poll cow.Born in Jedburgh as Lady Clare Kerr, Lady Euston is the fourth child of Peter Kerr, 12th Marquess of Lothian, and his wife Antonella (née Newland).Clare married James FitzRoy, Earl of Euston, son and heir apparent to the 11th Duke of Grafton, on 16 September 1972.He predeceased his father in 2009.Lord and Lady Euston had five children:She had previously been High Sheriff and Deputy Lieutenant of Suffolk. [SEP] Knowledge 2: Lyon Cohen
Lyon Cohen( 1868–1937) was a Polish- born Canadian businessman and a philanthropist.He was the grandfather of singer/ poet Leonard Cohen.

Answer: Captain Andrew William Kerr