She promised her son, the prince, that he will marry a real princess. She allowed the soggy princess in and covered her son's mouth when he said something rude and did a test putting a pea under her bed to see how she would sleep. She said it was the only way. The next morning, she celebrated as the princess succeeded the test because she didn't sleep well and can marry her son. Hearing this, the princess was furious and angrily said she didn't like the way he treats women and watches helplessly as she leaves.
the princess and the pea