Who's kissing Matt Damon? Luciana Barrosso, his wife of nearly eight years! The Hollywood couple said "I do" all over again Saturday, April 13 in a romantic vow renewal ceremony on the Caribbean island of St. Lucia, Us Weekly can confirm. The Promised Land star, 42, rented out St. Lucia's entire Sugar Beach Resort -- at a hefty six-figure price -- for the weekend in honor of the happy occasion; rumored invitees to the bash include Damon's BFF Ben Affleck and wife Jennifer Garner, among many other A-listers.

"This isn't a 'Hollywood' wedding," one insider tells Us. "Matt wanted it to be fun, happy and private. He felt like Luciana deserves this, first and foremost."

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Explains another source of the locale: "This is the perfect place for this wedding. You can [go] here for serenity."

The actor, director and Oscar-winning screenwriter first wed the Argentina-born former bartender, 36, in a private civil ceremony in December 2005. They share daughters Isabella, 6, Gia, 4 and Stella, 2 -- plus Alexia, Luciana's daughter from a previous marriage.

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"They've wanted to do it for a long time," another pal says of the vow renewal. "They had a tiny ceremony the first time, and wanted to celebrate with family and friends."

The Good Will Hunting actor has always been slightly more low-key in his personal life than his famous friends -- and he likes it that way. "The narrative about me kind of goes, 'He's a boring married guy,' which is great, because I don't get any of that other stuff like Brad Pitt and George Clooney do," Damon told Playboy late last year. "People think I'm kind of vanilla and they leave me alone to work, have an actual private life and be a husband and dad."

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Outnumbered 4 to 1 at home, Damon added that he doesn't mind being the only man in the house. "Lucy and the girls can definitely bring me to my knees."

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Although the vow renewal bash suggests otherwise, Damon claimed at the time that he was "sh--ty" with romantic gestures. "I wish I were better because my wife deserves somebody who surprises her with a gift or flowers or some wonderful idea . . . .I've never been good at that, and she's really good at it, which makes me feel even more like sh-t."

This article originally appeared on Usmagazine.com: Matt Damon, Wife Luciana Renew Wedding Vows in St. Lucia!