|Information in this article is non-canon|
Dayo is a Longneck. She is a Brachiosaurus, just like Shorty. Her parents were killed in front of her by hungry Sharpteeth. She got cut on her face by them but was able to get away. She was chased across the Mysterious Beyond through a desert by the hungry Allosaurus pack for over a day. Eventually, she came to the Great Valley where she passed out.
She was revived by Littlefoot and his friends. She was very paranoid, having a dread that Sharpteeth were coming out to get her. She was very friendly, albeit paranoid. She was also very clumsy and had the bad luck of getting on the wrong side of Topps and Mrs. Maia.