Will Kopelman and Drew Barrymore Credit: Eugene Gologursky/WireImage.com

Wedding and a baby!

Proud parents-to-be Drew Barrymore and Will Kopelman have plenty to celebrate these days; the pair--who got engaged over the holidays--are also expecting their first child.

The duo got together to fete their happy news with some of their closest pals in Los Angeles Saturday at the home of Leonard Goldberg, the producer of Charlie's Angels.

"Everyone was doting on pregnant Drew and asking her how she is feeling," a witness tells Us Weekly. "She is so thrilled to be expecting, and also really excited about the wedding."

Though she has yet to confirm her pregnancy--and has been careful to hide her growing stomach with loose, oversized clothing--Barrymore, 37, flaunted her bump with pride alongside her boyfriend of one year, who wasn't shy about showering his love of one year with affection.

Us first broke the news of Barrymore and Kopelman's engagement in January; three months later, a source confirmed that Barrymore is also set to become a first-time mom.

"Drew will be an amazing mom," the insider told Us. "She's seriously the coolest person in the world…Very generous and doting."

For his part, Kopelman can't wait to settle down with the Big Miracle star. Explained a source, "He's madly in love and knows she's The One."