I WAS shocked to read the competition slogan in the Sunday Young Post: 'T-shirts and film tickets to be won - Oliver Stone's Natural Born Killers brings two of the most terrifying mass murderers imaginable to the motion-picture screens . . .' The thought that some innocent children might win these T-shirts and walk around with Natural Born Killers emblazoned on their chests causes me to shudder. JEANETTE BRESNIHAN (Mrs) The Peak