Nicole Richie showed off her three-month-old daughter, Harlow , at Baltimore-Washington International Airport on Monday. Richie was traveling with beau Joel Madden , who is on tour with his band Good Charlotte. The new mom, who flaunted her post-baby bod in tight jeans and a loose sweater, browsed magazine racks while Harlow, in a gray-striped onesie, snuggled against her. Madden pushed the stroller, and even popped his daughter's pacifier in his mouth at one point. Harlow, who was born ...