Jenna Dewan and Steve Kazee are marking their “rainbow baby’s” first birthday.

Dewan took to Instagram on Saturday to celebrate the special occasion.

Posting side-by-side shots of Callum as a newborn and today, she wrote, “The fact that this little angel baby is one years old today is blowing my mind.”

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The “Step Up” star continued, “Callum, you came into this world and changed it the instant you were here…you brought with you pure joy, pure love and a little spark of the divine that i have a feeling will never leave.”

Dewan is also mom to Everly, 7, from her marriage to Channing Tatum.

The 40-year-old actress went on, “You bring everyone around you together like the bright shining sun and we all want to bask in it all day. It is an absolute gift and honour to be your mommy.”

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Concluding her post, Dewan added, “Your dad, Evie and I thank the universe for you every single day and we love you beyond our little rainbow baby!!”

A “rainbow baby” is often used to describe a baby born after a miscarriage. 

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Dewan and Kazee got engaged back in February 2020.