Baby-San is a dragon in the 1987 TV series. It appears in the episode "Usagi Yojimbo", and is kept inside a large case that protects it from damage. Obento is the guardian of Baby-San, and he treats the egg as though it were a child.
However, Baby-San was endangered when the Foot Soldiers stole his egg and dropped it into a smokestack, causing it to hatch. Baby-San grew immensely upon finding food (partly due to the Ninja Turtles) and attracted the attention of the military. He also learned to breathe fire, and used it indiscriminately.
However, Baby-San was rescued by the efforts of Usagi Yojimbo, who was given a blue candle by Obento and ordered to throw it in the dragon's mouth. When he did so, Baby-San was transformed back into an egg, and was returned to the animal sanctuary, where Obento continued to watch over him.