The Land Before Time II: The Great Valley Adventure

Littlefoot, Cera, Ducky, Petrie, and Spike live a carefree life in the Great Valley under their families' watchful eyes. One day, the gang attempts to get to the sheltering grass to play, but land in the sinking sand surrounding it. The adults rescue them and chastise them for their recklessness. The next night, the children have a secret meeting and decide to prove their bravery and maturity by venturing into the Mysterious Beyond, a location outside the Valley that is inhabited by Sharpteeth. Before they leave, they notice two egg stealers, Ozzy and Strut, stealing an egg from the nest of Ducky's mother. The children pursue the intruders into the Mysterious Beyond. An ensuing landslide damages the Great Wall that surrounds the Valley and protects it from the Sharpteeth, and the stolen egg rolls safely back to the nest, but the group do not notice this in the confusion.