02/17/2009 AT 11:10 AM EST
She's starred onscreen with Tom Cruise, Patrick Dempsey and Shia LaBeouf, but Michelle Monaghan said those films don't hold a candle to her new part – "the role of mommy."
The Eagle Eye
actress, 32, gave birth
to daughter Willow Katherine on Nov. 5. Three months later, "every day feels like Christmas," she told PEOPLE. "It's such a profound love. A couple of weeks ago I saw her discover her own toes and she wiggled them and her eyes got really big."
Monaghan ventured out on her own for a New York City amfAR gala Feb. 12. Leaving Willow at home in L.A. with husband Peter White was difficult for the actress. "It's my first night away from her," she says, "and I imagine I miss her more than she misses me."
Just three months after giving birth, Monaghan zipped herself into a sample size Louis Vuitton dress and donned four-inch heels for the amfAR event at Cipriani 42nd Street. Her body after baby secret?
"Honestly, I started working out after two-and-a-half months," she says. "I have a trainer. I've just been lifting weights and breast feeding. And I eat really healthy and a lot, because I'm breast feeding ... always organic. I frequent Whole Foods. I never really cared so much about my diet until I got pregnant and had a baby."
And when will Monaghan return to the screen? "I'm taking some time," she says. "Looking at some [projects], but enjoying being in the role of mommy."