How to annoy my mother - not that that was the intent.

How to annoy my mother - not that that was the intent. My parents, reasonably, prefer to have lights off in unoccupied rooms. My mom has made a big point of this. So now I habitually turn off lights in any room I go through that isn't occupied when I pass through it. However, my mom apparently wanted the lights on in the room next to the room she was currently ensconced in, but I didn't know that and turned them off when I walked through. After a brief dialogue on this subject, she said, "Only turn off the lights you've turned on." To which I replied, "I don't have that kind of relationship with the lights." My dad laughed. My mom made inarticulate noises of frustration and an aunty face.