Did it hurt?

Two six-year-old boys are standing in the toilet having a pee.
One turns to the other and says, “Your dinky doesn’t have any skin on it.”
“That’s because I’ve been circumcised,” he replies.
“Cor! What does that mean?”
“It means the skin’s been cut off the end.”
“How old were you when they did that?”
“About two days old.”
“Did it hurt?”
“It sure did. I didn’t walk for a year.”

First child

How can you tell?