The Princess and the Pea

He knew that only a real princess could feel a tiny pea under 20 mattresses and 20 quilts!

I tried to make the summery of this story.
One stormy night, a girl visited to a prince who was looking for a perfect wife, and she said " Hello, I am a princess. May I stay here tonight?" The prince accepted her. He made a bed for her with a trick. According this book, if she is a real princess, she must notice the trick. Actually, she noticed and finally, they get married.

Actually, I doubted the girl. Is she a real princess?
But  by using the tiny pea, the prince recognized the girl was real princess.
Whaat ....sounds crazy.