The Grandfathered star shared a black-and-white throwback pic that showed him with Olsen and her twin sister, Ashley, when they were kids.
"In the blink of an eye," Stamos, 51, captioned the nostalgic pic, adding "Congrats MK X."
The Olsen twins played Michelle Tanner on the hit sitcom, which ran from 1987 to 1995, and Stamos portrayed their Uncle Jesse.
While Mary-Kate and Ashley, both 29, are the only stars who didn't return for the beloved show's reboot, Fuller House, which debuts next year on Netflix, Stamos, who's an executive producer on the show, clearly doesn't hold a grudge.
Mary-Kate married her French banker boyfriend of three years on Friday, Nov. 27, at an intimate gathering at a private residence in NYC. Sarkozy, 46, proposed to the actress-turned-fashion designer in February 2014.
Bob Saget, who played the twins' father on Full House, revealed in an interview with Today on Monday, Nov. 30, that he didn't get an invitation to the nuptials.
"But I'm very happy, and I sent a mazel tov text," he said. "I love her very much, and I hope they're happy."
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