Freddie Prinze Jr.'s Happy Marriage to Sarah Michelle Gellar Is Thanks to His Cooking and Cleaning

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Freddie Prinze Jr. is dishing about what a 20-year happy marriage to Sarah Michelle Gellar looks like — and it involves, coincidentally, doing the dishes!

"I hate a mess. If something is dirty, I clean it," the Christmas with You star, 46, said during an appearance this week on Australia's The Kyle & Jackie O Show to promote his Netflix movie. "I do the dishes while I'm cooking so there's less s--- to look at."

He added, "I can't stand a mess: my room is spotless, my car is spotless. I'm one day late for a haircut and I'm going crazy."

The tidy actor also does the laundry and cooks all the meals in the Prinze-Gellar house. "My mom was a chef and I learned how to cook, and I married someone who couldn't cook," said the star, who is also a cookbook author. "So I'm necessary. She needs me to live and sustain herself."

And while Prinze also said he "still makes" Gellar, 45, laugh, there's one thing he hasn't done in 20 years of marriage: watch his wife's hit 1990s show, Buffy the Vampire Slayer.

RELATED: Sarah Michelle Gellar and Freddie Prinze Jr. Celebrate 20th Wedding Anniversary with Sweet Tributes

When the show's hosts asked him if he ever calls his wife "Buffy," he mildly rebuffed the question. "Not only have I never called her Buffy, I have never even seen the show," Prinze admitted.

He added, "I wasn't the demographic, in my defense. She was my girlfriend, then my wife [so] I've never called her that ever. We've been married 20 years, together even longer."

RELATED: Sarah Michelle Gellar Mixes Up Date of Wedding Anniversary: 'Thought It Was Tomorrow'

In September, the couple, who share son Rocky, 10, and daughter Charlotte, 13, celebrated their milestone anniversary with sweet social media tributes — and also jokingly tried to collect from radio host Howard Stern who bet Prinze $1 million ahead of their wedding in 2002 that their union wouldn't go the distance.

Sarah Michelle Gellar Instagram

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"Oh, absolutely it will last," Prinze replied to Stern at the time.

In her Instagram post marking their 20th anniversary, Gellar tagged Stern, 68, and tried to collect.

"What do you think? I think you owe us," she joked.

Christmas with You begins streaming on Netflix Nov. 17.