Like a kick in the head (Actually, not "like" at all.)

Guess why my son has this really nasty, gigantic bump on his head?

(A) He really wanted to be a unicorn for Christmas. Or a rhino.
(B) He was brained in the head by the school bully with a wooden car
(C) Voldemort stopped by, but messed up the scar.
(D) He had an encounter with the Przewalski's horse at Zoolights the other night.
(E) He is a klutz, falling down on a concrete step near the Capitol.

Despite (B) having actually happened earlier (see the other bump on his forehead, now almost healed) this time it's actually D. This confirms once again that he is, after all, my son.