In the book holes why does Stanley steal the water truck?

In "Holes" by Louis Sachar, Stanley Yelnats steals the water truck to help his friends at Camp Green Lake when they are suffering from extreme thirst during a particularly grueling day of digging. The boys have been forced to work under harsh conditions, and Stanley’s act is a desperate attempt to provide them with some relief. This act of rebellion underscores themes of friendship and loyalty that run throughout the story.