other source:
Gohan begins training for the World Tournament, and he takes Goten along. During the training, Goten reveals that he can become a Super Saiyan at nearly half the age Gohan did.Their training is interrupted by Videl, who has arrived to take her first flying lesson.He also reveals that Trunks is stronger then him.Vegeta also finds out that Trunks can also become a Super Saiyan.
