January Jones Welcomes Baby Boy

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The “Mad Men” actress has named her first son Xander, but the identity of the child’s father remains a mystery.

January Jones is now a mom.

STORY: 'Mad Men's' January Jones is Pregnant

A rep confirms to People that the Mad Man actress welcomed a baby boy on Tuesday, Sept. 13, naming him Xander Dane Jones. The first time mom opted not to learn of the baby's sex prior to giving birth, telling People in June, “It’s going to be a surprise for me.”

STORY: 'Mad Men's' January Jones Defended by Co-Star John Slattery

The 33-year-old star of X-Men: First Class announced her surprising pregnancy in April. The identity of the baby’s father has yet to be revealed.

Mad Men is scheduled to return to AMC’s schedule for Season 5 in March of 2012, following lengthy talks with creator/showrunner Matthew Weiner and due to the cable net’s packed slate. AMC also ordered a sixth round, with an option to extend the series to a seventh season.