Gwyneth Paltrow Celebrates 'Darling' Daughter Apple's 18th Birthday: 'I Could Not Be More Proud'

Gwyneth Paltrow/Instagram

Gwyneth Paltrow's daughter is celebrating a big milestone.

The Academy Award winner, 49, marked Apple Blythe's 18th birthday on Saturday, sharing a photo of the birthday girl posing in a mirror along with a heartfelt tribute on Instagram.

"18. I'm a bit of a loss for words this morning (😭). I could not be more proud of the woman you are. You are everything I could have dreamed of and so much more," she wrote in the caption. "Proud doesn't cover it, my heart swells with feelings I can't put in to words. You are deeply extraordinary in every way."

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"Happy birthday my darling girl. I hope you know how special you are, and how much light you have brought to all who are lucky enough to know you. Especially me. I say it all the time and I will never stop… in the words of auntie Drew, I was born the day you were born. I love you. ❤️ Mama," Paltrow added.

The actress welcomed Apple in May 2004 with ex-husband Chris Martin, with whom she also shares 16-year-old son Moses. Paltrow is also stepmom to her husband Brad Falchuk's teenagers, son Brody and daughter Isabella.

Paltrow previously revealed that it was Martin, 45, who came up with their daughter's unique name. "Her dad came up with the name and I fell in love with it. I thought it was original and cool. I can't imagine her being called anything else!" she shared last month during a Q&A on her Instagram Story.

Also last month, the Politician actress showed Moses some love for his 16th birthday, sharing an Instagram photo of her younger child admiring their balloon-filled house.

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"@Mosesmartin you are 16 today. I'm not sure how I'm writing that number," she wrote. "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."

Paltrow continued: "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. 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."