Gwyneth Paltrow is celebrating her son Moses.

The Oscar-winning actress, 48, penned a special birthday tribute to her 15-year-old son on Instagram on Thursday, sharing a look into Moses’ love of skateboarding.

“Holy Moses I can’t believe you are 15 today,” Paltrow wrote. “You are the dreamiest, sweetest, most brilliant guy ever. I love you so much, you can’t fathom it.”

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She added, “Happy birthday you little shredder 💙.”

Paltrow shares Moses and his older sister Apple, who will be 17 next month, with her ex-husband Chris Martin. The former couple divorced in 2016.

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Since their split, Paltrow and Martin have remained close, even hosting Sunday dinners together. Martin also makes the odd appearance on Paltrow’s Instagram page.

The “Iron Man” star is now married to Brad Falchuk.