In their birthday best! Kylie Jenner and her sister, Kourtney Kardashian, were spotted stepping out in style for friend Stephanie Shepherd‘s birthday in L.A. on September 14. Needless to say, the youngest and oldest Kar-Jenner sisters (respectively) looked totally stunning and ready to party. Oh, and they brought a few friends. Ky’s BFF Anastasia Karanikolaou and Khloé Kardashian‘s ex French Montana were also in attendance for the big bash. Scroll through the gallery to see photos of Kylie, Stassie, Kourtney and French out in Los Angeles.