Standing in the hallway as he was, Jon was unaware of the changes starting to occur.
The wish was granted, and the side effect started to assert itself. Jon noticed it as an odd blur effect across his vision very different from his previous wishes. It looked alot like the vertical wipe in a movie. When it cleared, instead of heading down the stairs, he was in the kitchen, holding a cup of coffee, which he nearly dropped.
Upstairs, sixteen year old Linda paused in the hallway and went back to her room and grabbed the wishing stone off the dresser. She stuck it into her bag and headed off to meet her best friend.