January Jones leaves baby's dad off birth certificate

It's certainly a mystery for the ages—at least, the digital ages—who is the father of January Jones' son?

Well, we got one giant step closer to discovering that today, as the birth certificate of Xander Dane Jones has been released. And while the "Mad Men" star is obviously listed as the mother, who's name is right alongside hers as the coparent?

MORE: Hear January's costars sound off on the baby daddy drama!

No one's.

1. More Entertainment stories
   1. Autistic ballerina dances her way into hearts
      

      In a popular YouTube video, the beaming little ballerina dances an entire four-minute routine seemingly perfectly, matchin...

   2. Every on-screen drink in 'Mad Men' in 5 minutes
   3. See the 'Dancing' stars' most memorable moves
   4. Emmy's biggest snubs? Cranston, Hamm, more
   5. 'Toy Story' toys burn up in prank on mom

View the birth certificate

That's right, don't go handing out those cigars just yet, because the ever crafty Ms. Jones isn't giving away the game that easily, and the document, filed Friday with the Los Angeles County Department of Public Health, was left completely blank in the spot that asked for the father's name.

Oh, she's good.

January has been keeping extremely mum on the subject of her baby daddy both before and after Sept. 13, when her bundle of joy came into the world.

Oh, well, mom and baby may are healthy and happy. And for now, Xander's the only man in January's life that we're gonna know about.

—Reporting by Claudia Rosenbaum

PHOTOS: Baby Bumpin'