A little girl asked her Mom, "Mom, may I take the dog for a walk around the
block?" Mom says, "No, because the dog is in heat." "What does that mean?" asked the child. "Go ask your father. I think he is in the garage."

The little girl went to the garage and asked "Dad, may I take Susie for a walk around the block? I asked Mom, but she said that Susie was in heat, and to come talk to you."

Dad said, " Bring Susie over here" He took a rag, soaked it with gasoline, and scrubbed the dog's rear-end with it and said, "Okay, you can go now, but keep Susie on the leash and only go one time around the block." The little girl left, and returned a few minutes later with NO DOG on the leash.

Dad asked, "Where is Susie?"

The little girl said, "She will be here in a minute, she ran out of gas about halfway down the block and another dog is pushing her home."