"I wish Zoe was at home."
His sister disappeared into thin air, scowling. One problem solved. It was really pretty easy, except that he knew that wishes were dangerous and he needed to avoid the temptation to overuse them. Now to deal with Mikey.
The wish was that he and Jon weren't brothers any more. "I wish that Mikey and me aren't brothers because Mikey is my sister, but she dresses as a boy and most people know her as Mikey anyway."
It suddenly got lighter, because the tree Jon was standing next to disappeared. His kid brother (?) was standing there. He looked normal, but he wasn't old enough for breasts to be too obvious anyway. "Now... I wish you remember everything you remember as my brother. All right, Mikey, that was a bad idea."
"I want a wish! Why didn't that work? It must not be real..."
"It was real enough, Mikey! You messed up. You messed up badly. I tried to get you back as close as you could be but you're a girl now. You're just not acting like it. It was your own fault."
Mikey slowly looked down and hit himself in the pants between the legs. "It's true... It was not my fault! What did you do?!"
"It was. When you wished we weren't brothers, it turned you into a tree. This is the best I could do to put you back considering that there's no way we could be brothers, and I wasn't going to change myself to fix your stupid wish. I was thinking of turning you into a car instead, you know. now let's go back inside."
"I'm a girl!"
"Nothing I can do about that. Do you want me to make you happy about it?"
"Hmph."