Gwyneth Paltrow Celebrates Son Moses' 16th Birthday: 'I Am So Lucky to Be Your Mama'

Gwyneth Paltrow is paying tribute to her son as he celebrates his 16th birthday.

On Friday, the actress, 49, shared a sweet post on Instagram in honor of her son Moses' birthday which included a heartfelt message to her younger child.

"@Mosesmartin you are 16 today. I'm not sure how I'm writing that number," Paltrow writes alongside a photo of Moses admiring his house filled with balloons. "Since you came into the world on that perfectly New York spring morning, you have made the world a better place. With every thought, action and intuition you have, you make people feel seen, heard and valued."

"You are deeply special to all who know you. I am so lucky to be your mama. I'm savoring every minute as you grow and change into this amazing man," she continues. "What a true blessing to have you, your wisdom, your kindness, and your beautiful singing voice ringing through our halls. You mean the world to me, my boy. Happy birthday."

Paltrow shares son Moses and daughter Apple, 17, with ex-husband Chris Martin. She is also stepmom to her husband Brad Falchuk's teenagers, son Brody and daughter Isabella.

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Back in September, the Goop founder honored Moses on National Son Day, sharing a cute selfie of the mother-son duo on Instagram.

"Total heart melter #nationalsonday," she captioned a photo of the pair riding together in an open air car.

The Shallow Hal star also celebrated her daughter Apple on International Women's Day last month.

"Happy international womens day. I've been spending the morning thinking about all of the incredible women I love, who love me back hard. I keep thinking about the women I have known since kindergarten or 7th grade, who are more strongly in my life than almost ever," Paltrow began her caption alongside a photo of her FaceTiming her daughter.

"But today I want to pay tribute to one (technically almost) woman on the cusp of it," she continued, speaking of Apple. "This woman gives me hope for the future of sisterhood, and for the future of our planet. And this woman has made me the woman I am today more than anyone else."