The Cry Babies miss their friends and ask Lora to travel to Tutti Frutti Bay on her boat and bring them all to Tropical Island for a party. They also request Sia to guide them, but she does not want to leave her rock alone for long because it was a gift from the volcano. Sia tells the Cry Babies that the volcano gave the rock to her one day when it erupted, and she had to sing a lullaby to make him fall asleep. She also tells them that if she sings opera, she can wake the volcano up. However, Fancy does not believe Sia and tells her to prove it. So, Sia begins to sing opera... and the volcano erupts! The Babies are shocked and tell Sia to put it back to sleep with her lullaby. But, the mermaid has lost her voice and can no longer sing... Will the Babies manage to stop the eruption?