What Happens When the Tooth Fairy Doesn’t Come?

So have you ever had a situation where the Tooth Fairy doesn't show up?  Here's the scenario.

You go to wake your child up in the morning.  Your child looks at you and says "I lost a tooth."

You are confused because child still had said tooth when he went to bed.

You ask, "where's the tooth."

The child then happily raises his pillow, and you see the tooth, then he sees the tooth and the child's face immediately turns to a frown.  "The Tooth Fairy didn't come."

So you in a fit of panic, "when did you pull the tooth?"

"In the middle of the night, I couldn't sleep"

"Well maybe the Tooth Fairy was already off work and you are on her list for tomorrow," you explain.

So what do you do when the Tooth Fairy doesn't come?