I remember hearing a story of a boy who was born without a philtrum, and he remembered all the Torah the angel taught him in the womb (Niddah 30b), and when he was brought to a Rav, the Rav said "this it not the way it is meant to be" (or something), and hit him on the lip, and he forgot.
What is the source of this story? I'd like to know who the Rav was and what the full reasoning was. Please summarise that point in the answer when you bring the source. Thank you.