Jeff Vespa/GettyImages.com 1 / 22
Jeff Vespa/GettyImages.com 1 / 22

Uncle Jimmy? Ali Larter is pregnant and expecting her second child with actor husband Hayes MacArthur. The actress made the announcement -- and showed off her adorable baby bump -- during an appearance on "The Tonight Show With Jimmy Fallon" on Friday.

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"Last time you were here was three years ago and you were pregnant on the show," Fallon said.

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"Yeah, I came on and it was pregnant and it went so well," Larter, 38, gushed. "So I told my husband I was going on Fallon so I gotta get pregnant!" The "Diabolical" star then jumped up to rub her growing belly.

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"It's such a scary time and I've been trying to hide it as much as I can," Larter admitted. "I was still shooting my [TV] spy drama [Legends] -- so I have to be a covert spy in my own life too. I've been wearing blazers and push up bras. Anything to distract my bump."

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The "Heroes" alum and MacArthur, 37, tied the knot in August 2009. Us broke news in December 2010 that they had welcomed son Theodore.

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