Role reversal

Lately our new campaign has been to get the children to turn their lights off when they come downstairs. Sometimes they do, sometimes they don't.

If I go upstairs and the lights are on I'll call them up (mostly C, since she can reach her light) to shut them off. Usually she runs up with an "OH! I'll go do that" and shuts the light off.

This morning, however she didn't.

I called down to tell her.

E39: C4, the light that I turned off for you earlier is on again. Can you come up and turn it off, please?
C4: No!
E39 & C40: No?? Why not?
C4: That's how I punish you!