The dog walker

This story is about a 17 year old girl named Carly, that walks another people's dog's for money. One day after Carly walks a neighborhood friends dog their dog later that day dies. There were no weapons or any suspicious things in the owners house but all the cops knew was that Carly was the last person the dog saw other than the owners. The twist is Carly knows who did it but she doesn't have enough evidence to prove she had nothing to do with it. Will Carly go to jail Or will Carly have enough evidence to prove her Innocents and find out who the true killer is? Find out in this book.