Kristin Cavallari's baby bump is finally starting to show!

The 25-year-old Laguna Beach star proudly displayed her pregnancy curves while hosting E!'s Academy Awards pre-show in L.A. Sunday, wearing a strapless gray dress and nude Christian Louboutin heels.

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"My stomach literally grew double overnight!" Cavallari, currently engaged to Chicago Bears quarterback Jay Cutler, tweeted Sunday. "This belly came out of nowhere!'

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The former MTV star recently told Us Weekly she's excited to become a first-time parent with Cutler, 28. "He's gonna be a great dad! He's so cute with kids," Cavallari said. "He's good with my little dog, so he's gonna be really, really cute with kids!"

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The on-again couple are eager to learn their child's gender. "I'm dying to know! I don't know how people wait," Cavallari admitted to Us. "I'm really excited!"

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