VIDEO : Leighton Meester Photographed for the First Time Since Giving Birth

Long time no see, Leighton Meester! The former Gossip Girl actress recently enjoyed a " girls' night " in the Valley with her best friends. The girls' night in marks the first time Leighton has been photographed since giving birth to a daughter, Arlo Day, with her husband, actor Adam Brody. The actress-turned-musician never discussed her pregnancy publicly, nor did she announce her firstborn child's birth. In fact, it wasn't until September that E! News confirmed the Life Partners co-stars became parents on Aug. 4 at 12:12 a.m. when Leighton delivered little Arlo at Whittier Hospital in Whittier, Calif.