Gisele Bundchen is one hot mama-to-be!

Strutting down the red carpet at the Museum of Fine Arts in Boston Wednesday night, the Brazilian-born beauty flaunted her growing (but still tiny!) baby bump in a black, ruched Halston dress and black Tom Ford jacket.

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The supermodel, who's pregnant with her second child, was on hand to celebrate the opening of pal Mario Testino's "In Your Face" photography exhibit, a collection of fashion photos and celebrity snaps -- some of which feature Bundchen herself.

Us Weekly first broke the news of the 5-foot-11 stunner's second baby-on-board back in June.

"Yes, she is pregnant," a source told Us, adding that the model was about "three months along" and "really happy."

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This will be the 32-year-old catwalker's second child with her husband of three years, New England Patriots quarterback Tom Brady, 35. The couple already have a 2-year-old son, Benjamin. (Brady also a 4-year-old son, Jack, from his relationship with Blue Bloods actress Bridget Moynahan.)

Bundchen has been tight-lipped about her pregnancy this time around, but in 2010, she opened up to British Vogue about wanting to expand her family.

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"I want more kids for sure, but I don't know when," she told the magazine. "For Benjamin, his big brother is his hero. Jack comes in and Benjamin has a big smile. He wants to follow him around. Anything he does, he's just in awe of him, like, 'Oh my God!'"

This article originally appeared on PICTURE: Gisele Bundchen Rocks Growing Baby Bump in Tight Dress