Angelina Jolie and Brad Pitt
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A source close to the couple tells PEOPLE that Angelina Jolie and Brad Pitt are "thrilled to be adding to their brood."
Jolie's baby bump was the buzz on the blue carpet Saturday as she stepped out in a curve-hugging black dress at the Film Independent's Spirit Awards with Pitt.
The Jolie-Pitt family currently consists of Maddox, 6; Pax, 4; Zahara, 3; and Shiloh, 1. Last week the couple's adoption of Pax was made official.
Adds a source close to the couple, "They are very, very happy."
