A 'Grandpa Hitler' refers to the act of finishing upon the upper lip in a clean, solid block
He could not hold it in any longer, and burst out laughing. She rushed away and was met with a strange image in the mirror, what she could only describe as a Grandpa Hitler.
When you fail at something in life (eg. failing an exam or not getting a job), go home and spend an hour just standing in the shower, propping yourself up against the wall with your eyes on your feet.
Caleb knew the only thing to do after he didnt get prefect was take a failure shower.