The question of Khloe Kardashian's parentage has reared up again - incarcerated sportsman O.J. Simpson's manager believes his client could be the reality TV star's biological father. Kim Kardashian's sister has been fighting paternity speculation for years, because she bears little resemblance to her siblings - and now she faces a new round of questions following Norman Pardo's new claims. He tells In Touch magazine that Khloe's mum Kris Jenner and Simpson were more than just friends when her then-husband Robert was the former American football star's legal representative. Pardo has no definitive proof that Khloe is O.J.'s daughter - but he insists she could be. He tells the publication, "It's all going to come out sooner or later. Khloe could be O.J.'s kid." And Simpson's manager reveals his client has never denied the fact he may have fathered Khloe: "Whenever I bring it up, he giggles." Pardo insists O.J., who is currently serving a nine-to-33-year sentence in a Nevada prison for kidnapping and armed robbery, had plenty of opportunity to get close to Kris in the years leading up to his murder trial, during which he was represented by Robert Kardashian. The manager adds, "They all took their vacations together. There was a lot of partying going on back then." And Pardo reveals the truth about Khloe's paternity could be revealed next month (Dec13) if a judge grants Simpson's request to be released pending a new trial. He has hinted that O.J. has plans to share more information about his relationship with the Kardashians as the 20th anniversary of the death of his wife Nicole approaches in 2014. Simpson was acquitted of his wife's murder.