A mother and her 5yr old son were flying Southwest Airlines from Kansas City to Chicago.
The son (who had been looking out the window) turned to his mother and asked, "If big dogs have baby dogs and big cats have baby cats, why don't big planes have baby planes?"

The mother, who couldn't think of an answer, told her son to ask the stewardess.
So the boy asked the stewardess, "If big dogs have baby dogs and big cats have baby cats, why don't big planes have baby planes?"

The stewardess responded, "Did your mother tell you to ask me?" The boy said, "Yes, she did...."
"Well, then, tell your mother that there are no baby planes because Southwest always pulls out on time.
Have your mother explain that to you."