There's definitely a family resemblance among the Kardashian and Jenner sisters. But there's one major area where they don't all look alike.
Both Kardashian and Jenner are clad in only in a white button-down shirt, but Jenner (notably wearing heels) towers over her older sister. The perfect caption for the photo reads simply "Twins."
It looks like Kardashian may have been the shorter member of that pair, too.