Popsugar Entertainment Halloween Mary-Kate and Ashley Olsen Halloween Costumes 14 Mary-Kate and Ashley Costume Ideas That Are Double the Trouble For Halloween October 28, 2017 by Kelsie Gibson View On One Page Photo 3 of 15 ADVERTISEMENT () Start Slideshow Share This Link Copy ← Use Arrow Keys → 3 Chloe and Riley, Winning London What to wear: A turtleneck sweater, crazy printed pants, boots, and a long trench coat. One of you should wear a hat. How to act: Chloe is extremely driven and acts like a leader, while Riley is more of a free-spirit and just a tad boy-crazy. Previous Next Start Slideshow HalloweenAshley OlsenMary-Kate OlsenNostalgiaHalloween CostumesPop Culture Halloween CostumesMoviesHalloween Costumes For Women