Bugaboo

Sienna Miller stepped out with her daughter Marlowe and their dog on a cold winter's day in London, England on Sunday (Dec. 9). 2012. The Girl star pushed the 5-month-old in a trendy Bugaboo stroller.  At one point, she let their cute little black dog off his leash, so he could enjoy a run around the park. Speaking to Harper’s Bazaar in the…