Sleeping in the feywilde is wrought with peril. Mortals who sleep in the feywilde are subjected to the whims or the rulers/ elder of whatever land they are in. Normally most fey creatures do not need sleep. Though they can enter into a sort of trance like state similar to sleep. Once asleep creatures may enter into the mortals dreams and little rest is to be had. Only if one requests and is given sanctuary is sleep safe.