bunk bed impasse

My big girls, who both sleep on top bunks in their room, are closing in on a month long ceiling fan standoff.

One insists it be on high because it is "too hot" in her room yet will only sleep under her pink fuzzy blanket.

The other requests it be off because it is "so cold" up there yet refuses anything more than her sheet.

They are at a true impasse.

At this point I'm trying to decide who to put my money on...