January Jones had a huge reason to celebrate on Monday as she marked a momentous occasion with a gorgeous throwback of her son, Xander.
The Mad Men actress revealed that her only child is now ten years old, sharing an unseen photo of him as a baby on her Instagram Stories.
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In the snap, little Xander looks so adorable as he gazes up at the camera while standing in the snow, kitted out in a furry jacket with a hood and striped trousers.
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Captioning the image, January wrote: "My baby is 10 today! My whole heart."
The actress has strived to keep her son out of the public eye as he grows up, and hasn't revealed who his father is, telling The New York Times back in 2013 that the information was only her "son's business".
Speaking on a podcast last year, January joked that Xander's father is Bradley Cooper after being asked if her child is "handsome".
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January shared a sweet throwback of Xander to mark his tenth birthday
"My son? Yes. Bradley Cooper-type! Hey, you don't know, he may be Bradley's!" she replied.
In a 2017 interview with Red, she spoke about the benefits of raising Xander around strong women, revealing that he was even born with only females in the room.
The star usually keeps her son out of the spotlight
"My younger sisters and my mom and my doula were in the room; my brother-in-law and my dad were next door. I only wanted women with me. Female energy," she told the magazine.
"It's good to have strong women around a man," she added.
"To teach him to respect women. He doesn't have a male person in his life saying, 'don't cry' or 'you throw like a girl'. All those [expletive] things dads accidentally do."
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