Kylie and Kendall Jenner are continuing to use Instagram for very sisterly purposes—mainly, as a way to troll each other. This weekend Kylie shared a photo of her and Fai Khadra posing arm-in-arm on the night of Diddy's 50th birthday party, simply tagging "@kendalljenner" in the caption. Fai and Kendall are close friends, and Kendall has joked about whether she should start a family with him ("everyone in favor of Fai and i starting a family say “I” ✋🏼"). He was also her date at Hailey Baldwin and Justin Bieber's wedding.