"Don't cartwheel into the fireplace."

Hmm, this one caught me by surprise. I hadn't imagined this ever needing to be verbalized (although I could probably say that about many things that slip out of my mouth). But, once again, there we were just minding our own business, doing our own thing, when suddenly we find ourselves in a situation where something weird is going on and some adult spurts out some gibberish that makes total sense. This time I was that adult. And I'm proud? surprised? relieved? to say that there was complete understanding from the child and absolutely no reaction from the other adult in the room.