Not very much is known about Jack's life growing up, other than that his parents are no longer with him. In the Newsies novel by Johnathan Fast, Jack finds a picture of his parents that they took in Coney Island, Brooklyn. Eventually, he finds the Newsies and becomes one himself.
Jack and Santa Fe
Jack dreams of going to Santa Fe, New Mexico. Even dedicating a song to it in the movie. During the movie, Pulitzer makes him a scab worker by giving him the opportunity to go to Santa Fe. He later stops being a scab worker and goes back to the strike. In the end, he is given another chance to go to Santa Fe when Teddy Roosevelt comes. In the original script, he takes this opportunity and goes to Santa Fe. But in the movie we have now, he turns back and stays in New York.