When I was a kid one of my friends taught his baby brother that his knees were actually called "balls". We thought it was hysterical when the poor kid would run in from falling over to tell his mother that he had hurt his "balls". His mother did not find it funny.
When I was a kid we had a cat called "Cat".
For some reason I have been thinking about these small pieces of my childhood today. I've come to the incredibly incisive conclusion that whatever they were labelled the boy's knees were not really his balls they remained his knees and If we had named the cat "Dog" it still would have been a cat.
Have other mners had similar experiences?