In the movie that Gabe, Bob and Amy are watching the President gives orders to blow up a supernova. The problem is that a supernova is a star that is exploding and you can not blow up an explosion in order to stop it from exploding.
While P.J. sneaking in the living room window, Charlie is staining her shirt with the Moroccan food. When Charlie turns around to laugh at P.J. after he gets stuck in the window, her shirt is completely clean. Once the rest of the family arrives home from the movies, however, Charlie's shirt is covered in stains again.