Having A Puppy_英语笑话

a little boy and his dad were walking down the street whan they saw two dogs having sex. the little boy asks his father: "daddy, what are they doing?" the father says: "they are making a puppy". so they walk on and go home.
a few days later, the little boy walks in on his parents having sex. the little boy says: "daddy, what are you doing?" the father replies: "making a baby". the little boy says: "well, flip her around! i'd rather have a puppy instead!"