The Land Before Time II: The Great Valley Adventure.

Littlefoot and his friends find life in the Great Valley a bit too restrictive under the watchful eyes of their overprotective parents. Wishing to not be treated like babies anymore, the group chase after a pair of dangerous dinosaurs stealing an egg from Ducky's nest. When the egg they bring back hatches in the valley, the friends are surprised to find a baby Sharptooth. Rather than abandoning him, they name him Chomper and attempt to raise him as one of their own.