Mikey closed his eyes. "I wish... there was a wishing stone on Jon's dresser exactly where I took this stone from that looks identical to the stone I took but that any wishes with it made things princess-y and magical like Cinderella or Sleeping Beauty or other Disney Princess stuff!"
There was a flash of light and heat and the stone in Mikey's hands was a cold, dead, grey. Turning it over in his hands he could see that a small part of the stone at the end retained its original color and luster. "I wish I knew what happened to the Wishing Stone!" Mikey said in a panicked whisper. "Oh, it'll be awhile before it can really do anything again."
Jon meanwhile shuts his bedroom door behind him and picks up the, unknown to him, new Princess Stone. "I wish that students at my school didn't have to do homework."