Before I get to chapter 4, I need to give a little quick background on chapters 1-3. Those chapters lead up to chapter four's mini climax.
Chapter 1 introduces the reader to Bud. He is a foster child, and he is being picked up that day to go to a new family.
Chapter 2 describes how Bud's new older brother, Todd Amos, is a real jerk. Todd picks on Bud, Bud retaliates, and Bud gets in trouble by horrible Mrs. Amos. She locks Bud in the shed outside.
Chapter 3 focuses on Bud's time in the shed. It's creepy and scary. He does manage to fall asleep. When he wakes up, Bud thinks that he sees a bat hanging above him. Bud takes a swing at it with a rake only to realize that it was a hornet's nest. Bud starts getting stung and bails through the shed window. Bud wants revenge on the Amos family.
Chapter 4 is about Bud's revenge. Bud sneaks into the Amos household and grabs his suitcase. He sets it outside in order to make a speedy get away later. Bud's next move is to stick Todd's fingers in a glass of warm water. Bud is trying to get him to wet the bed, since Mrs. Amos hates bed wetters. It doesn't work, so Bud pours the water over Todd's pajama pants. Victory! Todd wets the bed.
He smiled and the warm water from the jelly jar opened that little valve up and ... woop, zoop, sloop ... he soaked his sheets!
Bud then makes his way out of the house, grabs his suitcase, and runs away.