Perfect for children just learning to read, this highly original book is told entirely in speech bubbles with a repetitive use of familiar phrases. From the award-winning author of Don't Let the Pigeon Drive the Bus!Gerald is careful. Piggie is not.Piggie cannot help smiling. Gerald can.Gerald worries so that Piggie does not have to.Gerald and Piggie are best friends.Gerald begins to wonder if he is allergic to his best friend. Will he have to stay away from Piggie for ever...?! Mo Willems creates another hilarious escapade starring the award-winning duo that will have early readers breaking into laughter from the first page.