Babies

Matt Damon's Baby Is 'Smiling' Already

By Paul Chi

09/09/2008 at 10:30 AM EDT

Is Matt Damon's daughter a child prodigy? Not even three weeks after the birth of little Gia, the Oscar winner says his newborn is already "smiling."

Still, the proud papa admits, it could just be gas. "She smiles normally when she goes to the bathroom," Damon, 37, told PEOPLE in Toronto Monday night before hosting the annual OneXOne charity gala to fight against child poverty. "That's natural."

Gia joins big sisters Isabella, 2, and Alexia, 10. So how is PEOPLE's reigning Sexiest Man Alive handling fatherhood this time around?

"I sort of knew what to expect with the third girl," he said. "But I'm still on high alert all the time."

In fact, Damon is so notoriously nervous, he's even earned a nickname back home. "They call me 'Red Alert,' " he said. "If any of the kids were near anything close to being dangerous, I would say, 'Is she touching that?' or 'Watch out!' And the whole family would go, 'Red alert! Red alert!' I guess I can be a bit worried sometimes."

For the third year in a row, Damon served as emcee and auctioneer at the OnexOne gala. "It was a no-brainer," he says, "OneXOne is truly a wonderful foundation that is fighting to help stop unnecessary living conditions."

The organization works with and provides funding to top children's charities worldwide to aid impoverished and disadvantaged kids. "I think it's hard for anybody to feel anything but tremendous sympathy for children all over the world that are living in dire living conditions," the actor adds. "It makes you very angry as a parent."

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