The main character is probably Gideon. But depending on the nature of the story, there could be other important characters. For instance, if it's a story about Gideon at school, there could be a kind teacher or a best friend who plays a significant role in Gideon's journey. Another possibility is that there is an antagonist, like a mean kid who makes Gideon's life difficult.
We can assume that Gideon is a main character in this children's story. There may be additional characters that are crucial to the plot. It could be a magical creature that Gideon meets if the story has a fantasy element. Or perhaps there is a mentor figure, an older person who gives Gideon advice and helps him or her grow. Also, Gideon's pet (if he has one) could be an important character that accompanies Gideon in his adventures and provides some comical or heart - warming moments.