We All Scream For Ice Cream part1 

While Piper goes searching for her father, after hearing news that he's been seen in town, Prue is driven to learn the name of song whose melody is stuck in her head. She discovers the स्रोत is an ice cream truck.
कीवर्ड्स: चार्म्ड, piper, phoebe, prue, full episode 54, season 3