This is not the first time the tooth fairy forgot to leave money for a lost tooth.
This time, he lost his tooth at school. When you lose a tooth at school, you get to take home a tiny treasure chest to put your tooth in. Not surprisingly, Caleb lost his tooth (I mean actually lost his tooth) at school and brought home an empty treasure chest.
I tried to smooth things over by telling him that the tooth fairy probably didn't leave his reward because she didn't find his tooth. He wrote this letter for the second night.