And when we say act, we really mean her teeth!!
The young model took a break from clubbing with her sis and visited her trusty dentist Dr. Kevin Sands to get her chompers looked at, and they decided it was time for her to get braces!
But don't expect to see metal in Kendall's mouth anytime soon, because she opted to go with Invisalign instead!
Her doc gave us a rundown on her new gear, saying: