you know that i know that you know that i know

When you and/or your friend type something in a group chat that is related to something only you two know so you send the you know that i know that you know that i know and confuses everyone else

Friend 1: has crush on John

*in le group chat*
Friend 1: why the hell is John's name in there
Friend 2: you know that i know that you know that i know
Friend 1: ahh yes
Everyone else: i am confusion