Hércules: La Serie Animada 1x63

Pain and Panic plan to use water from the magical Spring of Cananthus in order to turn Hercules into a baby, and this time finish him off for good. Unfortunately, Pegasus, Icarus, and Adonis also get sprayed with the stuff, and it's up to Cassandra to play the role of mother and, along with Panic (and the newly infancized Pain), and return the boys to their rightful age.