Horsey ride

One day, little Mikey came home from kindergarten and couldn't find
his mother. So he headed upstairs and opened her bedroom door.

To his surprise, he saw his dad stripped naked on top of his mom, who
was also naked, both heavily into the sexual act. Not wanting to
traumatize the boy, the parents continued to do what they were doing.

After a couple of minutes, Mikey asked, "Daddy, can I climb on top and
have a horsey ride?"

The dad thinks for a second, "Of course son, we're a family."

After a couple more minutes his mother starts moaning and writhing wildly.

"Hang on Dad!" cries Mikey, "This is where me and the mailman usually fall off!"