question: Who is Alexander Of Courland's father?
context: [["Albert Visetti", ["Albert Anthony Visetti( 13 May 1846\u201310 July 1928) was a Dalmatian musician who moved to London where he was Professor of Singing at the Royal College of Music, becoming a Fellow in 1921.", "He was the stepfather of the novelist Radclyffe Hall."]], ["Albert E. Austin", ["Albert Elmer Austin( November 15, 1877 \u2013 January 26, 1942) was a Republican member of the United States House of Representatives from 1939 to 1941 and member of the Connecticut House of Representatives from 1917 to 1919 and from 1921 to 1923.", "He was the stepfather of Clare Boothe Luce."]], ["Alexander of Courland", ["Alexander of Courland  (18 October 1658 \u2013 1686), nicknamed \"Alexander the One-armed\", was a Baltic German prince and the brother of Duke Frederick (II) Casimir of Courland.", "He was the youngest son of Jakob Kettler (1610\u20131682), Duke of Courland and his wife Luise Charlotte von Brandenburg (1617\u20131676), eldest daughter of Prince elector Georg Wilhelm von Brandenburg.", "He was a member of the Kettler dynasty.", "Alexander served as an \"Oberst\" in a regiment of the Brandenburg-Prussian Army.", "On 26 July 1686, he was mortally wounded in the second siege of Buda during the Ottoman wars and died shortly afterwards near Vienna."]], ["Margravine Louise Charlotte of Brandenburg", ["Louise Charlotte of Brandenburg (13 September 1617 \u2013 28 August 1676), was a Duchess consort of Courland by marriage to Duke Jacob Kettler of Courland.", "She was the de facto ruler of Courland during the reign of her spouse.", "She was born to George William, Elector of Brandenburg and Elizabeth Charlotte of the Palatinate (1597\u20131660)."]], ["H\u00e9ctor Barrantes", ["H\u00e9ctor Barrantes Sansoni( 1939\u20131990) was an Argentine polo player.", "He was the stepfather of Sarah, Duchess of York."]], ["Charles Williams, Baron Williams of Elvel", ["Charles Cuthbert Powell Williams, Baron Williams of Elvel,( born 9 February 1933) is a retired business executive and a Labour peer.", "In his 20s he played first- class cricket while at university and for several seasons afterwards.", "He is the stepfather of Justin Welby, the Archbishop of Canterbury."]], ["Lolo Soetoro", ["Lolo Soetoro", "( EYD: Lolo Sutoro;; 2 January 1935 \u2013 2 March 1987), also known as Lolo Soetoro Mangunharjo or Mangundikardjo, of Indonesia was the stepfather of Barack Obama, the 44th President of the United States."]], ["Gerald Rudolff Ford", ["Gerald Rudolff Ford( December 9, 1890 \u2013 January 26, 1962) was an American businessman, creator of Ford Industries, and Republican politician who was the stepfather of U.S. President Gerald Ford and for whom Ford legally changed his name."]], ["Morris Harvey", ["Morris Harvey( 1877\u2013 1944) was a British actor and writer.", "A renowned character actor, he also wrote for the stage, including material for Broadway revues, in which he also appeared.", "He was the stepfather of film director Anthony Harvey."]], ["Jerrold Wexler", ["Jerrold Wexler( June 27, 1924 \u2013 November 10, 1992) was a noted American businessman and film producer.", "He was the brother of cinematographer Haskell Wexler and the stepfather of actress Daryl Hannah."]]]
supporting_facts: [["Alexander of Courland", 1], ["Margravine Louise Charlotte of Brandenburg", 0]]
evidences: [["Alexander of Courland", "mother", "Luise Charlotte von Brandenburg"], ["Louise Charlotte of Brandenburg", "spouse", "Jacob Kettler"]]
answer: Jacob Kettler