Super Mario World 2: Yoshi's Island
Yoshi's Island takes place many years before Donkey Kong, the first Mario game. Baby Mario and Baby Luigi are being taken to their parents by the Stork, but a Magikoopa named Kamek attacks it, kidnapping Baby Luigi and causing Baby Mario to drop to Yoshi's Island. Baby Mario lands on the back of Yoshi, who, along with seven other Yoshis, helps Baby Mario defeat Baby Bowser and rescue Baby Luigi.