DMK leader MK Stalin penned an emotional letter to his departed father and party leader M. Karunanidhi on Wednesday, asking if he could call him ‘Appa’ one last time. Five-time Chief Minister and leader of the DMK for 50 years, 94-year-old Karunanidhi breathed his last here owing to age-related ailments in a private hospital on Tuesday. "Rather than calling you as Appa, Appa, I have called you as Thalaivaray, Thalaivaray (my leader) more number of times. Can I call you as Appa once Thalaivaray," Stalin said in his letter