Ribsy by Beverly Cleary

Henry Huggins's dog, Ribsy, is hopelessly lost in a huge shopping mall parking lot. It's raining hard, the pavement is slick, horns are honking, and drivers are shouting. When Ribsy thinks he has found the Hugginses' new station wagon at last, he jumps in the open tailgate window and falls asleep, exhausted. When he wakes up find himself in the wrong car, lots of little girls pet him and make plans to give him a bath. All Ribsy wants to do is go home to Henry. Instead, he's about to begin the liveliest adventure of his life.