On Monday, the 52-year-old Welsh actress posted a gallery of rare throwback photos on Instagram in honor of her son's special day, including pictures of Dylan from when he was a baby up through his recent college graduation.
"Happy 22nd Birthday Dylan. Zero to 22! You are everything to me and everything is you. The joy you have brought to this world thus far, is immeasurable. I love you more than words can say ♥️♥️♥️♥️♥️," Zeta-Jones wrote.
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"Dylan my man! Happy 22nd! My goodness! Out of college, on your way, you're rocking! I'm so proud of you Dylan. Have a great new year! Your year! May it be the best! I love you! Dad," he wrote alongside a picture from his son's graduation.
Less than three months ago, the Zorro actress celebrated another major milestone with her son as he graduated from Brown University. At the time, she shared a photo of her son's commencement ceremony as Dylan wore his cap and gown.
In the sweet image, Zeta-Jones embraced him with a blissful look on her face as he smiled for the camera.
"Graduation congratulations to my boy, my pride, my joy, Dylan. I am inexplicably proud of you and I love you beyond words," she wrote.
Zeta-Jones has previously shared glimpses into Dylan's life as a university student. In October 2019, during his sophomore year, she captioned a sweet mother-son photo of the two at Brown, "On campus with my boy Dylan."