Walk the Dog
Little Johnny asked his mom if he could take their dog for a walk. The mother said, "Honey, I don't think that is such a good idea because the dog is in heat".
Little Johnny wanted to know what that meant. The mom wanted to avoid the subject so she told him to go ask his daddy if he could take the dog for a walk. Little Johnny found his dad in the garage and asked him about taking the dog for a walk. He said "That is probably not a good idea because the dog is in heat".
So, he asked his dad what that meant. The father really didn't want to explain so he got some gasoline and smeared it all over the dog's hindquarters and tail. He said "There, now it should be okay for you to take the dog for a walk".
About an hour later, Little Johnny returned home but he didn't have the dog with him. When his father asked where their dog was, Little Johnny replied,
"Oh, I guess she ran out of gas but don't worry, there's another dog pushing her home