Michael Douglas and Catherine Zeta-Jones.Photo: Dimitrios Kambouris/Getty

Michael Douglas and Catherine Zeta-Jones

After more than two decades of marriage,Michael DouglasandCatherine Zeta-Jonesare still going strong!

On Thursday, theKominsky Methodactor, 77, marked his and Zeta-Jones' 21st wedding anniversary on Instagram withan adorable tribute videoof their most memorable moments since tying the knot.

“Happy Anniversary my darling Catherine! I love you so much @catherinezetajones ❤️ #21years,” Douglas captioned the post.

In an April interview withWSJ. Magazine, Zeta-Jones, 52, saidthe secret to making their marriage lastis having lots of fun together. She also shared that “constant love and respect” and maintaining a “sense of humor” are key to marital success, according to the actress.

Zeta-Jones also asserted that no relationship is perfect, and experiencing ups and downs is “normal.”

“My husband and I spend a lot of time together because, unlike so many couples, we’ve never had a 9-to-5 job where it’s consistent,” Zeta-Jones explained. “… So we’ve had in our relationship huge amounts of time where we’ve been just us. We lived on the island of Bermuda for 12 years bringing up our kids. We respect each other’s space, and our humor is just long-lasting.”

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73rd Primetime Emmy Awards - Arrivals

In September, the couple sweetly celebrated their joint birthday on Sept. 25 with separate tributes on Instagram.

For his post, Douglas detailed the night he met Zeta-Jones at the Deauville Film Festival in 1998 and the instant connection they discovered. “I found out that she had the same birthday as me–tadaah!,” he wrote alongside an image of the two toasting at the event.

From L to R: Carys Douglas, Michael Douglas, Catherine Zeta Jones and Dylan Douglas in 2015.Dave J Hogan/Getty

Carys Douglas,Michael Douglas,Catherine Zeta Jones and Dylan Douglas

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Zeta-Jones opted for a simpler message alongside a recent photo of the two all dolled up. “Happy Birthday to me.Happy Birthday to him, Happy Birthday to my husband and his wife, Happy Birthday to me, and me, and me, and Michael. 😂😂,” she captioned the image. “Here’s to more years that we can celebrate September 25th together. Love you.😘”

source: people.com