Ronald was among many younger animals who were eying a playground built by the mammoth Manny out of ice for his expectant wife Ellie. Though he, along with the other youngsters wanted to play in it, Manny would not let them.
Soon after, a ground sloth named Sid, having adopted three baby Tyrannosaurus Rex, let his children play in the playground, but unknowingly opened the gate to the other young animals as well, who stormed through, Ronald among them. But the young animals soon found that the baby dinosaurs played rough, notably Ronald, who was catapulted away into the sky, landing in a nearby tree. Manny found Ronald, pulled him down and rushed over to the playground to find it destroyed.
As a shovelmouth, Ronald had a broad, flat mouth with large flat teeth and flappy ears, walking on four short-toed legs.