Zero Timeline and Summary

We get our first glimpse of Zero when Stanley arrives at Camp Green Lake and is introduced to the boys in D Tent. Mr. Pendanski tells Stanley that his name is Zero because "there's nothing inside his head" (5.33).
It turns out Zero doesn't know how to read. After some hole-digging, Stanley finally agrees to teach him – in exchange, Zero will keep digging Stanley's holes for him.
The other campers aren't too psyched that Zero is helping dig Stanley's holes, and they give Stanley a hard time about it. This results in a pretty nasty fight, after which Zero runs off.
Stanley finds Zero sheltered under the overturned Mary Lou, surviving on jars of a peachy liquid he calls "sploosh."
The boys stick together, and Stanley ends up carrying a really sick Zero up the mountain. As Zero gradually gets better, he tells Stanley about his past, and how he became separated from his mother. It's a pretty sad story.
Zero and Stanley return to camp and, after some major obstacles, they dig up the treasure and get to leave camp with Ms. Morengo, Stanley's lawyer.
After he gets his share of the treasure, Zero hires a team of private detectives to locate his mother. And it looks like it worked: in fact, the last image of the book is one of Zero and his mother.