question: Who is the maternal grandfather of Eysteinn?
context: [["Zhao Shoushan", ["Zhao Shoushan( 12 November 1894 \u2013 20 June 1965) was a KMT general and later Chinese Communist Party politician.", "He is the grandfather of Zhao Leji."]], ["Abd al-Muttalib", ["Abd al- Muttalib Shaybah ibn Hashim( c. 497 \u2013 578) was the grandfather of Islamic prophet Muhammad."]], ["Yrsa", ["Yrsa, \"YrseYrs\" or \"Urse\" (6th century) was a tragic heroine of early Scandinavian literature.", "She appears in several versions relating to her husband, the Swedish king Eadgils, and/or to her father and rapist/lover/husband Halga (the younger brother of king Hro\u00f0gar who received Beowulf) and their son Hro\u00f0ulf.", "The common claim in \"Beowulf\" studies that Hro\u00f0ulf probably was the son of Halga is taken from the Yrsa tradition.", "Several translators (e.g. Burton Raffel) and scholars have emended her name from a corrupt line (62) in the manuscript of \"Beowulf\", although this is guesswork.", "In the \"Ynglinga saga\", Snorri Sturluson describes her personality as follows", "(Samuel Laing's translation):Yrsa was not one of the slave girls, and it was soon observed that she was intelligent, spoke well, and in all respects was well behaved.", "All people thought well of her, and particularly the king; and at last it came to so far that the king celebrated his wedding with her, and Yrsa became queen of Svithiod, and was considered an excellent woman."]], ["Fred Le Deux", ["Frederick\" Fred\" Le Deux( born 4 December 1934) was an Australian rules footballer who played with Geelong in the Victorian Football League( VFL).", "He is the grandfather of Tom Hawkins."]], ["Eysteinn", ["Eysteinn (Swedish: \u00d6sten; died ca 600) was the son of Eadgils and Yrsa of Saxony.", "He was the father of Ingvar.", "The Eysteinn tumulus \"(\u00d6stens h\u00f6g)\" in V\u00e4ster\u00e5s near \u00d6stanbro has been linked to King Eysteinn by some popular historians.", "The term H\u00f6g is derived from the Old Norse word \"haugr\" meaning mound or barrow.", "Eysteinn ruled Sweden at the time when Hr\u00f3lf Kraki died in Lejre.", "It was a troubled time when many sea kings ravaged Swedish shores.", "One of those kings was named S\u00f6lve and he was from Jutland (but according to \"Historia Norwegiae\" he was Geatish, see below).", "At this time S\u00f6lve was pillaging in the Baltic Sea.", "He arrived in Lofond (probably the island of Lov\u00f6n or the Lagunda Hundred), where Eysteinn was at a feast.", "S\u00f6lve and his men surrounded the house and set it on fire burning everyone inside to death.", "Then S\u00f6lve arrived at Sigtuna (Old Sigtuna) and ordered the Swedes to accept him as king.", "The Swedes refused and gathered an army that fought against S\u00f6lve and his men, but they lost after eleven days.", "The Swedes had to accept him as king until they rebelled and killed him."]], ["Kaya Alp", ["Kaya Alp was, according to Ottoman tradition, the son of K\u0131z\u0131l Bu\u011fa and the father of Suleyman Shah, who was, in turn, the grandfather of Ertu\u011frul, and the great grandfather of the Ottoman Empire founder, Osman I."]], ["Henry Krause", ["Henry J.\" Red\" Krause, Jr.( August 28, 1913 \u2013 February 20, 1987) was an American football offensive lineman in the National Football League for the Brooklyn Dodgers and the Washington Redskins.", "He played college football at St. Louis University.", "He is the grandfather of Jennifer Krause", "He is the great grandfather of Payton Hoeing"]], ["John Mackay (poet)", ["John Mackay( 1656\u20131754), known as( The Blind Piper), was a Scottish Gaelic poet and composer, and the grandfather of William Ross."]], ["Lyon Cohen", ["Lyon Cohen( 1868\u20131937) was a Polish- born Canadian businessman and a philanthropist.", "He was the grandfather of singer/ poet Leonard Cohen."]], ["John Westley", ["Rev. John Westley( 1636 \u2013 78) was an English nonconformist minister.", "He was the grandfather of John Wesley( founder of Methodism)."]]]
supporting_facts: [["Eysteinn", 0], ["Yrsa", 1]]
evidences: [["Eysteinn", "mother", "Yrsa"], ["Yrsa", "father", "Halga"]]
answer: Halga