POPSUGAR Celebrity Halloween Mary-Kate Olsen and Ashley Olsen Halloween Pictures by Lindsay Miller 10/05/11 18 Shares Like us on Facebook Sign up for our daily newsletter > Follow us on Pinterest Previous Photo 1 of 11 View on One Page ADVERTISEMENT ( more slides) Next Share This Link Copy 1 Mary-Kate Olsen and Ashley Olsen Halloween Pictures Previous Photo 1 of 11 View on One Page ADVERTISEMENT ( more slides) Next Read More StyleMintHalloweenAshley OlsenMary-Kate Olsen Ashley Olsen The Full House Cast Really Loves One Another in Real Life The Olsens Just Made Their PFW Debut With a Stunning (and Superintimate) Presentation Ashley Olsen Just Pulled Off a Major Fall Style Hack John Stamos on the Olsen Twins Coming to Fuller House: "We Only Need One!" Halloween That Abandoned Wizard of Oz Theme Park? I've Stayed There The Poltergeist Curse: Here's the Real Story Behind the Movie Myth 9 Ways to Be Amy Schumer This Halloween 13 Nights of Halloween: Here's the Full Lineup For ABC Family's Annual Marathon! Mary-Kate Olsen Mary-Kate and Ashley's Latest Looks Are a Total '00s Throwback Mary-Kate Olsen's Bold Shoe Choice Is Not What We Expected Mary-Kate and Ashley's 75-Year-Old Muse Is About to Become Your New Style Icon 13 Moments That Made Us Wish We Had a Stylish Sister by Our Side POPSUGAR, the #1 independent media and technology company for women. Where more than 75 million women go for original, inspirational content that feeds their passions and interests. Be in the Know With OurCelebrity and Entertainment Newsletter Personalize Young Hollywood TV A-Listers Movies Sign up with facebook or By signing up, I agree to the Terms and to receive emails from POPSUGAR.