"I became whole because you came into this world," the 38-year-old actress shared.
Time flies!
January Jones took a trip down memory lane, revealing a rare photo of her son, Xander, in honor of his fifth birthday on Tuesday.
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"This one goes out to us my son…5yrs ago today I became whole because you came into this world," the 38-year-old actress captioned a photo of herself holding Xander as a baby.
Last month, Jones also shared another adorable photo of her little boy. "When the guy you love thinks you're cray but kisses you anyway," she captioned the adorable post.
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In April, Jones opened up about being a working mom and why there shouldn't be a stigma around single mothers.
"Being a mother is hard, no matter what your family dynamic is," Jones told the Daily Mail. "But I think it’s really healthy for a child to see mothers working, and also for women to have something personally and mentally to focus on other than a child."
Jones credited her friends with being her support system and stressed female empowerment. "We women beat ourselves up a lot, but I don’t listen to any of that. We should be supportive, not judgmental. Luckily, the friends I surround myself with are strong, so I’ve never had to deal with being criticized or having someone feel sorry for me," she explained. "I've never experienced any negative stigma. I think I'd laugh it off anyway."
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As far as work goes, Jones currently appears in the Fox comedy, The Last Man on Earth, and wrapped the final season of Mad Men last May.
Watch Jones and her Man Men co-stars talk about the series finale in the video below.