Anna Faris Reveals the Secret to Her Slim Post-Baby Body

USMagazine, Friday, December 14, 2012, 10:00am (PST)

There's only one person responsible for helping Anna Faris get her smokin' hot post-baby body back in record time: her 3-month-old son, Jack!

At the Zero Dark Thirty premiere in Hollywood Dec. 10, the first-time mom shared the secret to slimming down so quickly after her baby boy's premature Aug. 25 arrival. "I think it's from hauling around the little guy," the Tadashi Shoji-clad What's Your Number? actress told E! News. "I'm trying to do it without help, so it's been a lot of lifting."

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Faris' husband, Chris Pratt, is in awe of the star's rapid weight loss. "This is the second date night we've had since she gave birth just three-and-a-half months ago, which is really hard to believe looking at her," the  proud 33-year-old said.

"I have the sweetest husband," Faris, 36, chimed in. "He makes me feel good at any weight. In fact, I kinda think that he likes it when my butt is a little bit bigger!"

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"Yup, I'll take it!" laughed Pratt, who married Faris in 2009. "I like it. Don't work too hard!"

While Faris is getting back in shape, her hubby is doing just the opposite!  Pratt recently packed on the pounds for his role in the Vince Vaughn comedy The Delivery Man, formerly known as Starbuck.

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"I gained 60 pounds in about four-and-a-half months. I just did it the old fashioned way: eating and drinking my face off," he said on The Tonight Show With Jay Leno Dec. 10. "I've lost a little bit of it, but it was hard. It was probably just as hard as losing weight. You wouldn't believe it, but it is. It's these same principle: It's all about pain."

This article originally appeared on Usmagazine.com: Anna Faris Reveals the Secret to Her Slim Post-Baby Body