On the hit show Mad Men, housewife Betty Draper was known for being adept at keeping secrets from those around her. It turns out that the actress who played her, January Jones, is also pretty good at keeping secrets. During the filming of season 5, Jones was expecting, and the show had to hide her pregnancy in a frankly absurd way. At the time, it was assumed by fans that the actress must have been married or in a long-term relationship, but this was not the case.

Related: Which Movie Star Did January Jones Admit Was Her Childhood Crush?

In actuality, the father of Jones' baby was a mystery and remains one to this day, although she has joked around that a few celebs might be the father. So why is Jones so secretive about it? And who exactly is her baby daddy? Here's what fans are saying.

January Jones is known for her many roles, including her time on Mad Men and X-Men: First Class. In 2011, the actress made headlines after welcoming her baby boy, Xander Dane Jones. January Jones' son, Xander, is easily the light of her life, however, many fans wonder who the father is. Well, Jones has kept this a secret to this very day, making it clear that she wishes to raise Xander without a father figure.

Many fans have speculated the possibilities of her fellow co-stars, Michael Fassbender, and Jon Hamm being the father, all while wondering if her exes, Josh Groban, and Ashton Kutcher, could be Xander Jones' dad. It seems as if January isn't budging on the topic, however, last year she did joke about Bradley Cooper being the father after being asked if her now 10-year-old son was "handsome." The duo were even spotted on the red carpet at the 14th Annual Oceana SeaChange Summer Party benefit in Laguna Beach, California, which is quite a rare occurrence for January and Xander.

Updated on February 20, 2022: January Jones' son Xander is now ten years old, and she has successfully kept the identity of his father hidden from the public for all that time. Jones and her son recently volunteered at the Los Angeles Mission's Annual Thanksgiving event, where they served food and posed for some pictures.

A few months prior, they attended the SeaChange Summer Party (hosted by Ted Danson), an annual event that helps raise money to protect the oceans. It seems like January Jones has been teaching her son the importance of giving back. By all accounts, Jones is very happy being a single mom.

9 This Is What January Jones Has Said About Her Baby Daddy

In 2011, the then 33-year-old January Jones gave birth to her son, Xander, but she never revealed who his dad is. Not just that, the actress also said that she would be raising her son without a father figure entirely. In 2017, she told Red Online that Xander was better off without a father, explaining, "I only wanted women with me. Female energy." She isn't the first or last actress to keep her baby daddy a secret.

8 Fans Think This Is The Most Likely Father

January Jones starred in X-Men: First Class, which was filmed in 2010 and released in 2011. Her performance was criticized by some, leaving a number of people wondering how she got the part in the first place.

According to some fans on Reddit, Jones may have gotten the role by having an affair with the movie's director, Matthew Vaughn, and these fans claim that Xander looks just like him. However, this is simply a fan-fueled rumor (and a misogynistic one at that). While the timeline does indeed back up this theory, Vaughn is happily married to supermodel Claudia Schiffer and he has categorically denied these rumors.

7 Could January Jones' High School Boyfriend Be The Father?

From 1998 to 2001, January Jones dated Ashton Kutcher, who was one of her very first boyfriends. A lot of fans are speculating that they may have rekindled their romance and Kutcher could be Xander's dad.

Fans claim that Kutcher lives in Sioux Falls, South Dakota, which is where Jones also so happens to be from is from, linking the two together, ultimately leaving many to believe that Kutcher could possibly be the father. Obviously, this is pure speculation, but an interesting theory nonetheless.

6 Let's Take A Look At That Suspiciously Uncommon Baby Name

Xander is not a particularly common baby name. Accordingly, fans have noted that January Jones starred in the 2011 movie Seeking Justice, which was filmed around the time she got pregnant. Actor Xander Berkeley is also featured in the movie, leading some to suggest that he is the father.

While this is a solid theory, it just seems a tad too obvious. Plus, it really isn't unusual for celebs to give their babies unique names, most far weirder than "Xander".

5 Others Say This Actor Is Hiding Something

Some fans have spotted a supposedly striking resemblance between Jones' son and actor Jason Sudeikis. Jones and Sudeikis dated in 2010, so the timeline does add up.

Related: Here's Why Fans Don't Think Jason Sudeikis Cares About Harry Styles

When the Washington Post asked Sudeikis if he had anything to say about Jones' pregnancy at the time, the actor stuttered, "No, I... no, I didn't have anything [to say]."

4 This Long Term Boyfriend Is Also A Prime Suspect

Singer Josh Groban has been linked to several gorgeous actresses and January Jones is one of them. Although the pair dated from 2003 to 2006, some fans think they may have hooked up again in 2010. Groban said that his relationship with Jones was his "longest relationship ever", as reported by Good Housekeeping. Fans were confused by this remark since he only dated Jones for 3 years.

3 Could January Jones' 'Mad Men' Co-Star Be The Dad?

When January Jones gave birth, her Mad Men co-star Jon Hamm was quoted as saying "He's a cutie... He's visited [the] set quite a bunch." According to Glamour, Hamm had a soft spot for little Xander, which led fans to speculate as to whether he could be the dad.

This theory is buttressed by the fact that Hamm and Jones did indeed start dating once Mad Men ended and Hamm broke up with his long-term partner, Jennifer Westfeldt.

2 Some Fans Think It's January Jones' 'X-Men' Co-Star

While X-Men: First Class director Matthew Vaughn is one of the prime suspects in the January Jones baby daddy saga, others have suggested that it could actually be Michael Fassbender, who starred alongside her in the movie. Fans wrote in to E! Online to give their theories on the matter, and Fassbender's name popped up.

Related: January Jones Doesn't Do Normal Beauty Routines

Jones and Fassbender are rumored to have dated during filming, so this is a real possibility, albeit a totally unsubstantiated one.

1 January Jones Has Joked That Bradley Cooper Is Actually The Father

A decade after Jones gave birth - with the mystery surrounding it continuing - the actress is still not free from fan speculation. Subsequently, she has poked fun at the relentless theorizing and joked that Xander's dad is Bradley Cooper.

When appearing on Dax Shepard's Armchair Expert podcast last year, the host asked Jones if her son was handsome, to which she replied, "My son? Yes. Bradley Cooper-type! Hey, you don't know, he may be Bradley's!"

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