Meet January Jones' Newborn Son Xander

January Jones and her son Xander Jones are seen coming out of an office building in Los Angeles, Calif. on October 11, 2011 -- FilmMagic

Meet baby Xander!

January Jones gave the world a glimpse of her almost 1-month-old son on Tuesday when she was spotted leaving an office building in Los Angeles.

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The new mom stepped out in a white lace top and gold-trimmed sunglasses, while baby Xander looked adorable in a print onesie.

On Monday, the 33-year-old actress, who gave birth on September 13, was seen getting back to work on the set of "Mad Men."

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Despite a slew of online rumors and speculation about who the father of the actress' baby might be, January has remained mum about his identity.

For more adorable shots of moms and their little ones - including Sandra Bullock and baby Louis, Gwen Stefani and Kingston and Sarah Jessica Parker with daughter Marion - CLICK HERE!

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