While it's only been several months since the Duchess of Cambridge gave birth to Prince George, rumor has it that she may be pregnant once again, HollywoodLife reports.

Sources claim that during the premiere of "Natural History Museum Alive 3D," Kate Middleton was resting her hand on her stomach throughout the night, and other insiders are now coming forward saying that the Duchess is already three months along.

"She looked absolutely beautiful and glowing, and her hand rested only on her stomach for most of the night," an insider who attended the movie premiere told Star magazine. "There was definitely what seemed to be a little bump showing already. And William was so tentative to her, quietly whispering to Kate and asking if she wanted to sit down or needed a sip of water. It was so sweet."

Palace insiders reveal that the Duchess has only just confirmed the news of a second pregnancy with her doctor, and thus she and Prince William have yet to tell many people.

"Their immediate families are obviously thrilled beyond words when the couple told them news," the Palace insider told HollywoodLife. "The other royals, including William's grandmother, Queen Elizabeth II, were let in on Kate's wonderful secret during their Christmas lunch at Buckingham Palace on Dec. 18 - and the entire family is now sworn to keeping it quiet so that an official announcement can be made in the New Year."

As for a name for baby no. 2, Carole Middleton reportedly is hoping for Diana in honor of the late Princess Diana if the baby is a girl, or Elizabeth or Phillipa, and "Charles, Henry, Philip or Spencer" for a boy.

Click here to see a photo of Kate Middleton out in the park with Prince George, perhaps concealing a growing baby bump beneath a loose-fitting t-shirt.