"So…this happened. My gurl. Ageless. Timeless. Steppin' out with the young-uns to show em how it's done," Meloni captioned his post, adding the hashtags "#HBDBaby" and "#TalkAboutIt."
In the first two images in the series, Williams can be seen getting ready for her night out on the town, putting on a pair of black stilettos to compliment her attire for the evening.
Jared Siskin/Patrick McMullan via Getty
Follow-up shots then show the birthday girl wearing a festive tiara and embracing her husband in a big hug, before a video and image of the pair dancing with their two kids — daughter Sophia and son Dante — closes out the carousel.
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Meloni and Williams exchanged vows in 1995, and the actor told PEOPLE last year that while their marriage has stood the test of time, he credits his wife for making it last.
"We're doing good. It's her patience with me, and I really mean that. She's allowed me to grow at my speed, because she's always been more mature and more levelheaded in many ways," he said. "She paints and I go in her studio, and it just makes me happy. We have her work all over the house. She wants to buy art, and I'm like, 'I don't want that. I want yours.' "
"It doesn't feel like [we've been married for] 27 years," the star added. "When the hell did that happen?"
Meloni also explained that fatherhood with his wife by his side has brought him immense joy. "I always knew I wanted kids, as did my wife," he said. "My mother always used to say to me, 'I've learned so much from you kids,' and I didn't get it. Now I get it."
Added Meloni: "One is more of an old soul. I never used that term until they came out of the womb and I looked in their eyes. I was like, 'Holy cow, look at you. You're here to teach me.' As well as the other one, who's a young soul. It's ever-evolving and a complete fulfillment of my life."