It is bad to make people feel scared
Ursula is babysitting young children and it is time for them to go to bed.
Ursula wants the kids to stay in their rooms.
Ursula reads the children book after book until she sees that they are all sound asleep and tucks them in.
Ursula tells the children a tall tale about mysterious things that happen to children who leave their rooms at night and how they might vanish.
The children Ursula is babysitting sleep soundly in their beds and are of no trouble.
The children Ursula is babysitting are horribly frightened by the story and not only cannot sleep but wet their beds for fear of going to the restroom.