The keys to a long and healthy marriage aren’t rocket science, according to Catherine Zeta-Jones.

In a new interview with WSJ. Magazine the actress revealed the secret to her 20-year-marriage to Michael Douglas.

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“First of all, we have a lot of fun together,” she said. “My husband is 25 years older than me; that’s not a secret. With any relationship, it wouldn’t be normal if there weren’t any ups and downs.”

But, she added, “The constant is love and respect. We’ve never, ever lost our sense of humour, and we enjoy each other’s company.”

Zeta-Jones continued, “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. We’re either on or we’re off. I’m really working 16 hours a day, or I’m not. He’s doing the same, or not. 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 humour is just long-lasting.”

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And since lockdown, amid the COVID-19 pandemic, Zeta-Jones says, “I’m a big kind of European, three meals a day [person]. In the whole lockdown, I relished having my kids and my husband here for breakfast, lunch and dinner.”

She and Douglas have two children together, son Dylan Michael Douglas, 20, and daughter Carys Zeta Douglas, 17.

In November, the couple celebrated their 20th anniversary recalling how they first met in posts on Instagram.

Read Zeta-Jones’ full interview at WSJ.com.