Little Johnny, Doctors and nurses

[rebbonk]

A woman brings eight-year-old Johnny home and tells his mother that he was caught playing doctors and nurses with Mary, her eight-year-old daughter.

Johnny's mother says, "Let's not be too harsh on them..... they are bound to be curious about sex at that age."

"Curious about sex?" replies Mary's mother.

Spoiler:

"He's taken her appendix out!"