Question: Who fathered Helena Sverkersdotter of the country holding in 2013 the league having the sports team joined by Marcus Mårtensson?

full_context: Document 1: 2014 Superettan: The 2014 Superettan, part of the 2014 Swedish football season, was the 14th season of Superettan, Sweden's second-tier football league in its current format. The 2014 fixtures were released on 20 December 2013. The season started on 5 April 2014 and concluded on 2 November 2014.
Document 2: Marcus Mårtensson: Marcus Mårtensson (born 23 April 1990) is a Swedish footballer who plays for Stafsinge IF on loan from Falkenbergs FF as a midfielder.
Document 3: Yolanda of Poland: Blessed Yolanda of Poland (also known as Helen; 1235 – 11 June 1298) was the daughter of King Béla IV of Hungary and Maria Laskarina. She was the sister of Saint Margaret of Hungary and Saint Kinga (Cunegunda). One of her paternal aunts was the great Franciscan saint, Elizabeth of Hungary.
Document 4: Helen of Sweden (13th century): Helen of Sweden ( 1190 – 1247, Swedish: "Helena") was a Swedish princess and abbess, daughter of King Sverker II of Sweden and the mother of Queen Catherine of Sweden. She was Abbess of Vreta Abbey.
Document 5: 2015 Superettan: The 2015 Superettan, part of the 2015 Swedish football season, was the 15th season of Superettan, Sweden's second-tier football league in its current format. The 2015 fixtures were released in December 2014. The season began on 3 April 2015 and ended on 1 November 2015. A total of 16 teams contested the league.
Document 6: Jonas Lundén: Jonas Lundén is a Swedish former footballer who last played for GAIS in Allsvenskan. He notably also played for IF Elfsborg and IFK Göteborg. Lundén played as a forward early in his career but at Elfsborg he was reschooled as a winger and full back. In 2001, he played one game for the Sweden national football team. He received a degree of fame amongst football computer game fans as one of the best prospects in SI Games' - one of a golden generation of Swedish youngsters who found fame outside of Sweden due to the cult football management game.
Document 7: 2013 Superettan: The 2013 Superettan, part of the 2013 Swedish football season, was the 13th season of Sweden's second-tier football league in its current format. The 2013 fixtures were released on 18 December 2012. The season started on 6 April 2013 and ended on 2 November 2013.
Document 8: Tobias Nilsson: After the season had finished Nilsson told the club that he wanted more playing time and when Superettan club Örebro SK made a bid for the midfielder he decided to sign with them in January 2013.
Document 9: 2009 Superettan: The Superettan 2009 was the ninth season of Sweden's second-tier football league. The season began on 11 April 2009 and ended on 24 October 2009.
Document 10: Johan Mårtensson: Johan Mårtensson (born 16 February 1989) is a Swedish footballer who plays as a midfielder for Örebro SK in Allsvenskan.
Document 11: Daniel Majstorović: He started his career with IF Brommapojkarna in his native Sweden. After a year with the club, he moved to German side SC Fortuna Köln in 1997, subsequently moving back to Sweden just a year later when he signed for Västerås SK. His form then earned him a move to Malmö FF, where he won his first trophy, the 2004 Allsvenskan, and his first international call-up for the Swedish national team in 2003.
Document 12: Victoria, Crown Princess of Sweden: Victoria, Crown Princess of Sweden, Duchess of Västergötland (Victoria Ingrid Alice Désirée; , born 14 July 1977) is the heir apparent to the Swedish throne, as the eldest child of King Carl XVI Gustaf. If she ascends to the throne as expected, she will be Sweden's fourth queen regnant (after Margaret, Christina and Ulrika Eleonora) and the first since 1720.
Document 13: Örebro SK: The 2003 season under new coach Stefan Lundin started well for Örebro, but yet again a poor ending of the season saw the team end up in eighth place. Promising goalkeeper John Alvbåge and Danish veteran Lars Larsen introduced themselves and soon became favourites of the Örebro crowd. The 2004 season became one of the darkest years in club history. First, Örebro had to fight hard to avoid relegation. A heroic effort with five straight wins at the end of the season earned a mid table finishing (seventh, later amended to eighth), but in the end effort proved futile. Economic problems had haunted ÖSK for a period of time as the club faced major deficits. Even after yet another heroic attempt by both supporters and sponsors the club was relegated by "Elitlicensnämnden" (eng: The Elite license board), who ruled that the balance sheet of the club did not comply with the standards of the Swedish Football Association. Örebro SK's appeal failed and the club was forced to play in Superettan.
Document 14: Helén murder: The Helén murder () is a sadistic murder of 10-year-old Helén Nilsson in Hörby, Sweden, in March 1989. The murderer, Ulf Olsson, the so-called Helén man ("Helén-mannen"), was convicted in April 2005, having been found after a DNA test in 2004.
Document 15: Juanan: After his contract with the Galicians ended, Juanan joined another side in the third level, Real Madrid Castilla, appearing in 29 games (all starts) in his second year as the Real Madrid reserves fell short in the promotion playoffs. In late June 2011, he moved to Germany and signed for Fortuna Düsseldorf.
ground_truth: Sverker II of Sweden
sub_queries: Marcus Mårtensson >> member of sports team Answer: Falkenbergs FF
Falkenbergs FF >> league Answer: Superettan
2013 Superettan >> country Answer: Sweden
Who fathered Helena Sverkersdotter of Sweden ? Answer: Sverker II of Sweden