He Says, She Says

I must preface this by saying that this conversation started completely out of the blue as Colin was going to the bathroom.  My favorite part of our conversations is how they generally start out of thin air.  So he calls out to me from the bathroom:

Colin: Mom, when you do one thing before you do something else, why is that called "first"?
Me:  That is just the word for it.
Colin:  Who made up that word?
Me:  It's just a word in the English language.
Colin:  Who made up the English language?
Me:  (googles "history of the english language" and begins to rub temples)  Honey, that is a long and complicated answer.
Colin:  (thinks momentarily) Do I get to add words to English?
Me:  Probably so.