"I don't want to be a teenage mother, Jon," said Karyn.
"I think I can fix that," he replied.
"Wait. Don't make another wish. At least, don't make one without thinking first."
"Don't worry, Karyn. I know exactly what to do. I wish Karyn was ten years older." The stone glowed. "See, now you won't be ... Karyn? Where did you go?" Jon looked around his room, but Karyn was gone. "I wish I knew where Karyn went." The stone glowed and suddenly he had his answer.
Since Karyn was now in her mid-twenties, she was no longer Jon's friend. So, it wouldn't make sense for her to be in his bedroom.
Karyn heard Jon's wish, so her memories didn't change to fit the new reality. Immediately after Jon wished her to be older, she suddenly found herself in an unfamiliar house. A minute later, she heard the front door open and then went to see who was coming in.
It was ...