Why are you bringing a baby doll to school?

In our home, the kids are expected to do their homework right after dinner. Occasionally, when I'd sit down with Joey and go through his backpack we'd find that he'd forgotten his reading book. Without this book he can't do a good portion of his homework. To help him stop "forgetting" I had to implement a rule of him showing me the inside of his backpack as soon as he walked in the door. If he didn't have his book, then he would get no computer or television privileges (by the way, he has only forgotten once since his day of "nothing to do" and he realized I was serious). A few weeks ago he came in the door and gave me his backpack. I looked inside and this is what I saw. I started laughing and asked him why he was bringing a baby to school. He got really upset and adamantly denied putting it there. Trent said that he'd seen Rachael carrying his backpack around the night before calling it her purse. Obviously we didn't check his backpack before he left for school the next day. It wasn't until poor Joey got to school that he discovered this baby doll. I asked him if he'd shown it to the class for show-and-tell. He didn't like my teasing and turned red, but shyly admitted a few of the kids in his class had seen it. I guess it's not nice to laugh at him, but that boy, and his expressions crack me up.