Put in my place

"I need my bed"  the boy's usual way of telling me he wants to go to bed.  We talk a bit about day camp tomorrow and he says again "I need my bed".  "Ok" I say, "goodnight Baby".  He turns towards his bedroom then comes back to me and in his halting speech says "I'm not baby.  I Donovan"

S'cuse ME!  Where did this come from?!  We then had to have a conversation that flew way over his head that even when he was a big big man even bigger than the tall teenager he is now, he will ALWAYS be my baby.  Then I smacked him upside his head for growing up. (ok I didnt but it crossed my mind)