See Kourtney Kardashian's revealing outfit for sister's 18th birthday party (Photos)

The oldest Kardashian, Kourtney Kardashian turned up the heat in an ultra sexy jumpsuit for Kylie Jenner’s 18th birthday.
Scott Disick and Kourtney went through a bitter breakup a few months ago, after having three kids together — Mason, 5, Penelope, 3, and baby Reign, 7 months.
another picture below