The boy wasn’t the one who was screaming, it was the grandfather.
The first shot didn’t hit anything, including the snake. The second shot hit and killed the snake and went on to pass through the boy’s head and immediately kill him.
Oh, please. You're pretending there weren't seventeen shots from the grassy knoll.
I know he wasn’t screaming, I was pointing out that the article itself says they heard the boy screaming. That’s a good indication that somebody isn’t telling the truth (either the reporter or the police).