Kim and Khloé Kardashian share reactions to Mason Disick's Instagram debut.Kourtney Kardashian's eldest son, Mason Disick, has officially joined the Instagram scene, marking a milestone in his teenage journey. On Saturday, May 25, born to Kourtney and ex Scott Disick, made his grand... Kim and Khloé Kardashian share reactions to Mason Disick's Instagram debut.Kourtney Kardashian's eldest son, Mason Disick, has officially joined the Instagram scene, marking a milestone in his teenage journey. On Saturday, May 25, born to Kourtney and ex Scott Disick, made his grand...