Title: The Land Before Time III: The Time of the Great Giving
A nearby meteorite crash blocks off the dinosaurs' water supply, starting an ecological chain-reaction that threatens life in the valley. All the dinosaurs, including a group of stupid bullies, must cooperate in an effort to free the blockage, which involves a risky venture outside the valley.
Roy Allen Smith
Dev Ross (screenplay), Judy Freudberg (characters), Tony Geiss (characters)