Gordon Ramsey tells PEOPLE his wife Tana “wants another” kidThe couple is already parents to daughter Megan, 25, twins Jack and Holly, 23, daughter Matilda (“Tilly”), 21, and son Oscar, 4Tana says she “doesn’t want Oscar growing up on his own”

The Ramsay family could be expanding soon.

In this week’s cover story, Gordon Ramsay tells PEOPLE, “Tana wants another one.”

Gordon, 56, and his wife Tana, 49, are already parents to daughter Megan, 25, twins Jack and Holly, 23, daughter Matilda (“Tilly”), 21, and son Oscar, 4.

“I’m going to be at school celebrating sports day with a f—ing walker!” Gordon says, laughing. “‘Hey, who’s your granddad?’ ‘That’s my dad, actually.’ So I’m not too sure how many knee hip replacements they’ll get by the time they get 21, but I’m going to try.”

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Gordon Ramsay with Tana, Holly and Oscar in London.

Zoe McConnell

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The Kitchen Nightmares star says Tana is itching for another baby not only cause “it’s an exciting thing” but “she says she doesn’t want Oscar growing up on his own,” reveals Gordon.

“On his own? He’s at school every day, and he’s got his four siblings! So, oh man, watch that space. . . . I’m f—ed.”

Gordon and Tana Ramsay.

Zoe McConnell

Tana tells PEOPLE that she always wanted a big family. “I’m one of four, Gordon’s one of four, so it’s sort of second nature to me,” she says.

It helps that her kids are “very cool,” she adds. Gordon happily boasts about his children.

“Jack’s a Royal Marine commando, off defending the country in some of the most extreme conditions,” he says. “Megan’s an incredible police officer. Holly’s gone into fashion. Tilly’s studying at university for her degree. Tana and I came from a family with no degrees.”

Gordon Ramsay with Jack, Holly, Tana, Oscar, Megan and Tilly.

Courtesy Ramsay family

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And their youngest Oscar (who was born three years after Tana suffered a pregnancy loss at 20 weeks) is “a cool kid,” says Gordon. “He’s only 4, but he’s grown up rapidly because of his four older siblings.”

As the adult children — who share their father’s passion for biking, hiking and swimming — have gotten older, Gordon has realized the importance of taking the time to listen.

“My job as a dad is to come up with a solution to their problems. That’s the most important role of a dad,” he says. “But boy, that’s f—ing hard with five kids, five problems, 25 a week, a hundred a month—that’s a lot of solution fixing.”

Gordon Ramsay with son Oscar, 4.

Zoe McConnell

The kids aren’t afraid to push his buttons either.

“If they want to tell me I’m wrong or they want to critique the food, I laugh,” he says. “Tilly was talking about one of the dishes last week, and I said, ‘Look, there’s caramelized garlic.’ And she got her fork in there and said, ‘Dad, it’s burnt. Caramelization is not black. Look it up in the dictionary.’ I’m like, ‘Oh my God.’ So, yeah . . . I like it when they test me.”

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