Kourtney Mary Kardashian (born April 18, ) is an American television personality, socialite, With sisters Kim and Khloe, Kardashian co-owns and operates D-A-S-H, a clothing boutique in Los Angeles, Miami, New York City, and a. The oldest of the Kardashian sisters is Kourtney born April 18,. She is one year older than her younger sister making her a firstborn or a. Please find below all Second oldest Kardashian sister answers and solutions. All crossword clues are solved daily!.