Bowser Jr. first appears in "Super Mario Sunshine", where he disturbs Mario's vacation with Princess Peach on Delfino Isle by making the island dirty and kidnapping Peach. He makes himself look like Mario, so the people of the island put Mario in jail. He kidnapped Peach because Bowser made him think that Peach was his mother, and he had to keep her safe. He later finds out that Peach is not actually his mother, but he still wants to fight Mario again in the future to make his father proud.