Popsugar Fashion Halloween Costumes 2019 Neil Patrick Harris and David Burtka Dressed as Olsen Twins Neil Patrick Harris and David Burtka Went All-In on Their Olsen Twins Halloween Costumes 2 November 2019 by Karenna Meredith View On One Page Photo 4 of 10 ADVERTISEMENT () Start Slideshow Share This Link Copy ← Use Arrow Keys → 4 Mary-Kate and Ashley Olsen Wearing All-Black Previous Next Start Slideshow Halloween Costumes 2019Celebrity Halloween CostumesDavid BurtkaHalloween CostumesNeil Patrick HarrisMary Kate OlsenAshley Olsen