Whenever the bed covers are a mess, "Oh no!"
Whenever there are some new writings on the wall, courtesy of him, "Uh-oh."
When something dropped on the floor, accidentally or not, "Oh no!"
When there is a new hole on the window screens because he pushed a crayon into it, "Uh-oh."
When his food dropped on the table or on the floor, "Oh no!", because he hates messes as much as Mommy does.
In certain scenes of his two favorite movies, Cars 1 and Cars 2, Johan says "Uh-oh" and "Oh no!" in great timing.
It is so cute and Johan says it with just the right facial expression and tone that anybody within hearing distance would surely end up laughing.