Author's note: This post incorporates ideas from a related branch episode by burke rakers, but takes a different spin on it.
Michelle had paused only for a moment outside on the driveway, wondering why there was no sign that her wish had worked. Why had that boy turned into a girl? That wasn't part of her wish, was it?
Hearing the noise from the front door, she leaped onto her pink Honda Metropolitan scooter and zoomed down the driveway. As she did, she made one more wish. "I wish I lived in a huge elegant mansion and could afford to live in places like that." The stone glowed, and the scooter passed one of her neighbor's houses. A 'For Sale' sign suddenly was present in the neighbor's front yard that had not been there a few seconds ago.
"Something totally crazy is going on with this thing." Michelle said to herself.
Karyn, meanwhile, had arrived just in time to see Michelle speed out the driveway on her scooter. Karyn leaped into her car (as she had used her car to get to Jon's house) to chase after Michelle.
Michelle spotted Karyn's car coming after her. She didn't want Karyn grabbing the stone away before she figured out what was up with it. The stone was the answer, if she used it right. She was a pretty smart person, and knew she could figure it out with more time and more wishes.
"Maybe something specific, like ... I wish Karyn's car would break down right now." she said. The stone glowed, and the wish was granted.
It was granted to the only person within 50 feet of Michelle, which happened to be Karyn herself. With a gasp, the car gave out, and Karyn was only barely able to pull over before it stopped completely. Karyn knew she'd have to try to catch Michelle on foot, and to do so she'd have to hurry.
She watched Michelle zip around a corner, and started sprinting after her with a speed that'd make an Olympic athlete proud. She cut across many neighbor's yards, between houses. Fortunately, the streets were wide and looping, and Karyn was able to keep Michelle in sight.
Michelle, meanwhile, saw how Karyn's car had broken down. She was surprised that it actually worked.
Why had that wish worked while the others hadn't? Why had that boy turned into a girl when Michelle wished to be the richest girl in the world? How had Karyn managed to make the boy appear in the first place by using the stone?
Then an idea hit her. She decided to make another wish on the stone.