Demis Maryannakis/Splash News Online
just gave birth
a few months ago, but you wouldn't know it by looking at her.
Wearing a flattering pink gown by Donatella Versace, Hudson, 28, told PEOPLE at the Whitney Museum Gala in New York Monday night that her secret to slimness is simple but ongoing.
"I'm still working on it," the Oscar winner said, adding that she walks 45 minutes to an hour every day. "I'm eating right, exercising, cutting sugar out of my diet. That's pretty much it, and walking every day, making sure I do some kind of exercise."
While she was performing at the gala, her little bundle of joy, David Daniel Otunga Jr., was being cared for at home by Daniel Sr.'s mother – and working on the kind of things babies work on.
"He's the cutest thing in the world," Hudson said. "He's working on turning over."
Then, whipping out her iPhone Hudson eagerly shared a picture of the beaming baby. "He honestly tries to talk. I sit and try to have conversations with him," she said. "Really, no words come out. But he doesn't know that. He's trying."
Little David's not the only one undergoing changes. Noted Hudson, "Motherhood has made me more affectionate, emotional."