Anne Hathaway Jokes She Forgot About Physics When Going Down a Slide with Her Son: I Was 'Shaking on the Inside'

"You know how it is when you've just almost killed your child but you didn't?" Anne Hathaway joked on The Tonight Show Monday

Anne Hathaway has been a mom for a little over a year now, but there are definitely still moments where she’s learning the parenting ropes.

Stopping by The Tonight Show Monday, the Colossal star admitted she may have bitten off a little more than she could chew recently when she took her 1-year-old son Jonathan Rosebanks down a slide at a N.Y.C. park.

“I noticed the kids weren’t going that fast so I thought, ‘Okay, I’ll bring Johnny on the slide,’ ” Hathaway told Jimmy Fallon. “So I get to the top of the slide — and just for any girls in the audience, [I was] in a skirt, which was dumb — so I pull the skirt around me and I put Johnny there, and we’re going down the slide, and now the moms are watching.”

“But what I hadn’t thought about was physics,” continues the 34-year-old Oscar winner. “So you have a 35-lb. child going down, it’s one speed, you have me and my son, it’s like … not 35 lbs., so we just go around the corner and instead of slowing down like the other kids, we speed up.”

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“And as it speeds up, my thoughts slow down, and I just look ahead and I get very serious and very focused and I think, ‘I must stick this landing,’ ” she says, miming her sliding position to the laughter of Fallon and the audience.

“So I shoot off the slide with Johnny and I go … ” Hathaway continues, reenacting the “sticking” position she took upon exit from the ride as the audience erupts in applause. “Stuck it. Stuck that landing.”

She adds, “And you know how it is when you’ve just almost killed your child but you didn’t? You’re shaking on the inside, you’re like, ‘Walk it off, walk it off, everything’s fine.’ And then we went back to the swings and stayed there forever.”

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Hathaway shares that Jonathan was backstage during her Tonight Show appearance, explaining that he’s cruising — he can walk with assistance, but not on his own quite yet.

As for her son’s first birthday party, she and husband Adam Shulman kept it fairly low key, with cake, sandwiches and games of cornhole.

“I think people have crazy expectations nowadays,” she says. “I was looking for a birthday present for him — don’t laugh, in an antique store — but anyway, I wanted to get him a little keepsake.”

“Babies love antiques,” Fallon jokes.

“Oh my God, you know what goes great with babies? Dust,” Hathaway replies with a laugh.