There was a 10 year old boy walking down the sidewalk dragging a flattened frog on a string behind him.
He walked up to a house of ill repute and knocked on the door.
When the Madam answered it, she saw the little boy and asked what he wanted.
He said, "I want to have sex with one of the women inside. I have the money and I'm not leaving until I do."
The Madam figured, why not, so she told him to come in. Once in, she told him to pick any of the girls he liked.
He asked, "Do any of the girls have any diseases?"
Of course, the Madam said no, but the boy replied, "I heard all the men talking about having to get shots after making it with Amber.
So THAT'S the girl I want!"
Since the little boy was so adamant and had the money to pay for it, the Madam told him to go to the first room on the right. He headed down the hall dragging the squashed frog behind him.
Ten minutes later he came back, still dragging the frog, paid the Madam, and headed out the door.
The Madam stopped him and asked, Why did you pick the only girl in the place with a disease, instead of one of the others?
He said, "Well, if you must know, tonight when I get home, my parents are going out to a restaurant to eat, leaving me at home with my babysitter. After they leave, my babysitter will have sex with me because she just happens to be very fond of little boys. She will get the disease that I just caught.
When Mum and Dad get back, Dad will take the babysitter home. On the way, he'll jump her bones, and he'll catch the disease.
Then when Dad gets home from the babysitters, he and Mum will go to bed and have sex, and Mum will catch it.
In the morning when Dad goes to work, the Milkman will deliver the milk, have a quickie with Mum and catch the disease .. and HE'S the B*****d that ran over my frog!"