Julia Roberts shared the secret behind her successful marriage that's spanned nearly two decades during an interview on The Late Show with Stephen Colbert.

The beloved actress is gearing up to celebrate her 20th wedding anniversary with her husband Danny Moder this summer. When late-night host Stephen Colbert asked her what her secret was to a successful and happy marriage, Roberts was able to respond with one word.

For Roberts, the answer is "kissing."

Colbert, who has been married for 28 years, responded with "apologizing." Frankly, we think both celebs shared some worthwhile advice. However, Colbert joked that his guest might be onto something.

"Well, I would like to apologize to my wife for not saying kissing," he said.

The Pretty Woman star teased him right back. "Well, or maybe you apologize and then you just start making out," she recommended.

You can check out the interview below. The segment about marriage advice starts around the 2-minute mark:

Based on a quick glimpse at Roberts' Instagram, it's pretty clear that she takes her own advice very seriously. This Valentine's Day, she shared a photo of herself and her husband smooching. The simple but romantic photo had a red heart drawn over top of it to showcase their bond.

Check it out below:

Roberts and Moder met while working on the set of a movie and were married in 2002, according to Hello! Magazine. The couple share three children together.

While Moder is not a fellow actor, he works as a cinematographer and camera operator. Aside from The Mexican, the film on which he and Roberts met, he has also worked on projects such as Mr. & Mrs. Smith, Mona Lisa Smile, Spider-Man 3 and Dead to Me, according to his profile on IMDb.

Fans will likely recall that Mona Lisa Smile starred Roberts alongside the likes of Kirsten Dunst, Julia Stiles and Maggie Gyllenhaal. How cool would it be to work with your significant other?

Roberts has paid tribute to her husband several times on social media. The star shared a sweet pic to commemorate their 19th anniversary in 2021. "Just getting started," she wrote in the caption.

Check out the pic below:

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