Littlefoot befriends with a mysterious, fun-loving dolphin-like creature named Mo, who is trapped in "new water" caused by heavy rain. The gang then goes on an adventure to the "big water" to bring Mo home.
The Land Before Time II: The Great Valley Adventure
The Land Before Time XI: Invasion of the Tinysauruses
The Land Before Time III: The Time of the Great Giving
The Land Before Time X: The Great Longneck Migration