DMK chief MK Stalin's son and actor Udhayanidhi has been appointed the party's youth wing secretary, a position that his father held for 35 long years - even after becoming a grandfather. The 42-year-old actor is managing director of the family-owned Murasoli Trust that runs the DMK's mouthpiece Murasoli, founded by his grandfather and former chief minister M Karunanidhi. Udhayanidhi Stalin is the fourth member of the Karunanidhi family occupying key positions in the party.