Hugh Grant has a surefire way to make his kids laugh — by putting his underwear on his head.
“I think it’s always amusing to put your underpants on your head,” says the father of four to PEOPLE’s editor-in-chief Jess Cagle in the latest episode of The Jess Cagle Interview (streaming now on People TV).
And it’s not just underwear that gets put on his head. “My little girl, too, likes nappies on my head,” he adds.
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And although the Paddington 2 star — who is expecting his fifth child, his third with Eberstein — says that he too enjoys putting undergarments on his head, he notes that there has been one unfortunate consequence of this amusing behavior.
“I made the mistake of showing one of my sons my ass all the time. ‘Hey, look at this!’ Then he taught every single child in West London to do the same,” he jokes.
Still Grant, who became a father for the first time in 2011, says having children is “the nicest thing that’s ever happened to me.”
“It’s just lovely to have all that love around,” the actor explains. “Suddenly you love someone more than yourself. It’s unheard of in my case. And they love you, and it’s all enchanting.”
And that’s partly why Grant doesn’t constantly “go rushing around for work.”
“I have 400 children and so many other things in my life,” he says, adding that “what’s nice is when work comes along, it tends to be a bit more challenging. I’m too old and ugly to be the young leading man in romantic comedies now, thank God.”
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And while Grant says he didn’t decide to star in Paddington 2 just because he thought his kids would love the film, for the most part they all do. But one of his sons thinks there’s a major problem with the movie — his dad’s in it too much.
“One of my sons said to me the whole way through, ‘Why are you in it so much?’ ” the actor confesses. “That was hurtful.”
Paddington 2 hits theaters Friday.
For more from Hugh Grant, pick up the latest issue of PEOPLE, on newsstands Friday.