Lucky number

Here is a conversation between mother and her daughter on "lucky number:

Daughter: I don't like school.
Mother: Why not? What is wrong?
Daughter: I don't like Gym class. I don't like recess. I don't like anything.
Mother: O.K. What else you don't like?
Daughter: I don't like my classroom. I don't like room 17.
Mother: Why not?
Daughter: 17 is not my lucky number.
Mother (with a perplexed look on her face): How do you know that 17 is not your lucky number?
Daughter: My fortune cookie told me. :)