Kylie Jenner is "back at it again." At least that's what the new mom captioned a recent photo of herself showing off her postbaby figure in a crop top sweater and lace-up pants after giving birth to baby Stormi Webster last month. On Saturday, Kylie stepped out with her best friend, model Jordyn Woods, to attend Tristan Thompson's 27th birthday party, but first, the reality star spent the afternoon bonding with her daughter and sharing sweet videos on Snapchat. It was a busy day for Kylie, who also attended big sister Khloé Kardashian's baby shower that evening. Keep reading to see more photos of Kylie's sexy night out.