When Laverne is defending her father to his mother, she says that her father gave up a new TV in order to make this visit to see her, emphasizing "You know how much he likes 'The Untouchables'". Penny Santon, the actress playing his mother, appeared on 4 episodes of 'The Untouchables'.
Though the festival is never mentioned by name, the timing of these 2 episodes being aired in mid-September indicates that the festival is clearly the feast of San Gennaro.
A movie theater has PSYCHO starring Janet Leigh and Anthony Perkins displayed on their marquee.