The Bratty Stone

The stone he put in its place looked just like Jon's stone, except there were creases around the sides, making it almost look like a small pumpkin. This was the Bratty Stone, and any time a person makes a wish on it, one aspect from the closest person to the wisher would get transferred from that person and into the wisher. Moreover, whatever aspect transfers, it will always be something the target valued greatly. The Bratty Stone doesn't care whether the wisher wants said aspect. It just doesn't like to see other people with things they like.