Ender is 6 to 12 all through the book. Ender is fierce, tough, intelligent, and emotional. He beat up a kid at school which he always remembered. He was chosen to go to Battle School to train for war. He became a leader at battle school for a group. He was transferred to command school to be able to command the entire army for war against their enemies named buggers. He wins the war for the humans.
Valentine was 8 years old in the beginning of the story and later becomes a young adult at the end of the book. Valentine is sensitive, caring, thoughtful, and intelligent. Valentine makes Ender remember why he was chosen to go to battle school and that he shouldn't give up. She helps Peter become a political influencer. She later crates an account that makes her famous without many people knowing it's her. Moves with Ender to an other planet.
Peter is 10 at the beginning of the book and 77 at the end of the book. Peter is strong, mad, and smart. Peter almost kills Ender in the beginning of the book. He threatens to kill Valentine. Peter later makes an account as an adult named locke that makes him famous. He becomes a great leader down in Earth and wants to make Ender work for him.