What is the exposition of Diary a Wimpy Kid last straw?

The main story of "The Last Straw" begins just after the summer before seventh grade. Greg Heffley's parents announce that they are going on a three-day vacation to a Sandals resort in Jamaica, and Greg and his older brother, Rodrick, will have to stay at home with their grandma and take care of the house. Greg is initially upset, but he eventually realizes that having grandma and his dad gone will give him a lot more freedom.