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James, you are the father! Or at least, that's what January Jones likes to say. It's never been confirmed who is the biological father of the "Mad Men" actress' son Xander, 2, and now James Marsden is admitting that he, in fact, is! (Well, not really.) During an interview with Playboy magazine, the "30 Rock" guest star joked that Jones is always calling him out for fathering her baby boy.

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"Every time I see January, she's like, 'Hey, father of my baby,'" the 40-year-old actor told Playboy in its latest issue.

The reason? Apparently, rumors once surfaced that the two conceived together because they both starred in (separate!) "X-Men" movies.

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"There's so much stupid talk out there," the Hollywood hunk explained. "I think that came from somebody thinking we were both in X-Men so it must be true." Marsden appeared as Scott Summers/Cyclops in "X-Men" in 2000, "X2" in 2003 and "X-Men: The Last Stand" in 2006. Meanwhile, Jones, 35, played Emma Frost in "X-Men: First Class" in 2011.

Jones welcomed Xander in September 2011. She previously dated Jason Sudeikis, Ashton Kutcher and singer Josh Groban, but has never revealed the identity of her son's father.

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"It's just not something the public needs to know. I don't divulge my sexual preferences," the Emmy-nominated actress told Net-a-Porter's The Edit in May. "There are parts of your life -- no matter what your job -- that should remain private."

She also reasoned that keeping the father a secret will help people just focus on her professional work. "As an actor, if people know too many things about you they won't believe you in a certain character," she explained. "You don't want people to have a preconceived notion of who you are."


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