But while they are covered up in their latest photo op they appear more grown up than ever, and RadarOnline.com has the stunning pics.
Sporting ball gowns and big hair for the family shoot Kylie, 14 and Kendall, 16, look years older than they really are.
The pair were clearly proud of their transformation as Kylie uploaded the snaps to her blog.
"We have a fun family photo shoot today and we're busy getting our hair and makeup done right now by our amazing team," she wrote, alongside a series of images including a number of snaps of her alongside her mother, Kris Jenner.
"Can't tell you what for yet….but you'll find out soon!"
Despite being members of the famous Kardashian clan both daughters are making names for themselves in the modeling world.
Kylie has graced the pages of a number of glossy magazines including Teen Vogue and OK! and Kendall made waves recently with her bikini shoot for Flavor magazine.