As an additional safeguard, put a smoothing iron under your bed.
Can I use the flat iron I use on my hair?
My husband, for some strange reason, would always use these diaper pins on the fitted sheets. Must have been something from his childhood when they either didn't have fitted sheets, or they weren't made well.
The faerie folk must have influenced them, because about a dozen times when coming around the corner of the bed I would stab myself with one of the damn pins that had popped open.
However, I did tell him if he ever puts diaper pins through the fitted sheets again, I'd hit him over the head with a cast iron skillet, so maybe there's something to it.