"My love for you is an ache and an honor," the Sex and the City star wrote on Instagram

James Wilkie is all grown up!

Sarah Jessica Parker celebrated her son's 18th birthday by sharing never-before-seen family photos to mark the milestone.

Alongside a slideshow featuring pictures of James through the years, including several featuring Parker holding the boy, the Sex and the City star, 55, wrote on her Instagram, "October 28th, 2020. My beloved son, James Wilkie, On this day, you are 18 years old."

"I marvel at the passing of those years but equally the young man you are becoming. My love for you is an ache and an honor," she continued. "As you leap toward and into your future, I remain your privileged and steadfast confident and joyful witness to the year ahead."

"Happy birthday my first time voter," the actress concluded the tribute. "I love you so. X, Mama."

Parker shares James with husband Matthew Broderick. The couple are also parents to twins Tabitha Hodge and Marion Loretta Elwell, 11.

In 2018, the shoe designer told PEOPLE she's very proud of the people her children are growing up to be, revealing that her son in particular has "this great friend group."

"Sometimes I just sit on the stairs because they’re all in the kitchen, eating all the food, and I listen," she shared. "And I’m so charmed by their conversation. I’m so happy with the young man he’s becoming."

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Parker also revealed that she has started saving sentimental items from her life to pass onto her kids.

"I think, 'Oh, I hope James Wilkie finds someone special to give this to' — a necklace my husband gave [me], or my books. Or my letters from people that are special or important," she explained. "I think those are the things I think more so about them receiving in some way."

As for her legendary wardrobe, Parker said she has set aside some pieces for when her children when are older.

sarah jessica parker and family
Sarah Jessica Parker and Matthew Broderick with their kids in 2017
| Credit: Walter Mcbride/Getty

Sarah Jessica Parker and Matthew Broderick with their kids in 2017

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"I expect that at some point I will give them my shoes and my concern is that they’re gonna be taller than me and they’re gonna fit the shoes at the wrong time," Parker shared. "They'll do with them what they want — they can give them away, share them with friends, sell them, have a stoop sale, whatever they want."

"I think things that I saved are obviously sentimental professionally or personally and they can do duke it out and figure that out."