Popsugar Fashion Spring Fashion Mary-Kate and Ashley Olsen Wearing Birkenstocks The Olsens Are Twinning For the First Time in Decades March 25, 2014 by Leah Melby View On One Page Photo 2 of 10 ADVERTISEMENT () Start Slideshow Share This Link Copy ← Use Arrow Keys → 2 River Island metallic silver cork pool slides ($53) Previous Next Start Slideshow Ashley OlsenMary-Kate OlsenSpring FashionFashion TrendsGet The Look