Jon's pleading didn't stop his mother from uttering her wish. A wish that the now teen mom had no belief could happen.
"I wish I was your little sister so I could torment you" she said.
Nothing seemed to happen, of course.
"What did you do?" yelled Jon's 16 year old mother. "I made a wish! It didn't work! I was supposed to be a child!"
"Mom," said Jon, "you don't want to be a child without being able to change back... but it doesn't matter. You already wished to be teenage, so you can't become non-teenage by turning into a kid. So you're staying just as you are!"
"But the wish..."
"You must be my little sister now. I'm 17, you're 16 or so. That's younger than me, you're my little sister. You know, since Dad died a long time ago, I wonder how we're living now. Are we just living alone without any parents?"