Knock first!

The other day Julia was instructed to turn off the TV and do her chore. But when I came into my own room, there she sat, her eyes glued to the TV, probably watching Hanna Montana or Zack and Cody. And what was I greeted with but, "You're supposed to knock first!!!" Isn't this MY room, MY TV? Aren't you supposed to be doing your chore? Isn't the TV supposed to be OFF? NO. I am supposed to KNOCK FIRST before entering my room. Huhhhhh. My mistake!