JKR World Book Day Chat said:Ernie: I wonder if you can let us know what form will Professor Snape's Boggart and Patronus take? I am very curious.
JK Rowling replies -> Well, I'm not going to tell you Ernie, but that's because it would give so much away. I wonder whether Ernie is your real name? (It was my grandfather's).
Came across this as I was looking for something - anyone wanna guess what JKR is trying to say here?