Each Time I Got Up From Bed I Always Notice

Each time I got up from bed I always notice that my pillow smells like a very bad odour because I've been drooling while asleep. I've tried putting a wrapper on top of my pillow so I won't stain it but I just can't stop it even when I brush before going to bed and try not to eat late. It's really embarrassing to me because I can't let my children come closer to my pillow for fear of smelling it.