The stars celebrated Halloween last night and with parties over the weekend. HIMYM's Alyson Hannigan and husband Alexis Denisof dressed in matching dragon costumes with their kids while Lauren Conrad went as Mary Poppins. Rebecca Gayheart wore a ghost outfit with her daughter Billie and Calista Flockhart matched with Harrison Ford. There were even more celebrities in costumes, so click through to see them all!
Stars Celebrate Halloween in Costume!