On Sunday, the Sex and the City star, who turns 56 on Thursday, shared an Instagram tribute to Broderick for his birthday, posting an out-of-focus photo of his cake with lit candles.
In the post's caption, Parker wrote, "Happy birthday Husband. We love you and we are oh so happy, grateful you were born. XXX, your SJ and 3 besotted young Broderick's."
She then shared a clearer snapshot of the brown frosted cake on her Instagram Story, adding "We love you so."
The Hollywood couple tied the knot on May 19, 1997, and share three children together: twins Tabitha and Loretta, 11, and son James Wilkie, 18.
Sarah Jessica Parker/Instagram
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During an appearance on SiriusXM's Quarantined with Bruce in November, Broderick opened up about his relationship with Parker. When asked what the secret is, Broderick joked, "I keep reading 'communication,' and 'she's my best friend.' Uh, any cliché you want?"
"I don't know the secret at all," he admitted at the time, "but I, you know, I'm very grateful and I love her. It's amazing. I mean, I can't believe that it's been that long. It doesn't feel like it. And I can't believe my son's 18."
Jenny Anderson/WireImage Matthew Broderick and Sarah Jessica Parker
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Speaking with PEOPLE back in 2018, Parker opened up about the couple's relationship dynamic.
"It seems so silly, but I think you're very lucky if you like the person," she said. "I still just really like him. I'm sure I annoy him and he annoys me, but I literally learn about him every day. I'm like, 'You're doing what? You're reading what?' "
"I think marriage has a lot of vitality," added Parker. "If you're fortunate, it's like this dazzling organism."