S.L.
He may be stuffy because he has allergies, it is allergy season. My son is now 20 mos and I found out last summer that he is allergic to many things and dust mites is among them. They get worse in the spring b/c it gets warmer and damper. I used the humidifier for a long time b/c he was always stuffy then the allergist told me that was the worst thing I could do b/c it creates the ideal environment for dust mites to breed making his allergies worse! I stopped using it immediately as well as getting an air cleaner for his room and keeping it very clean. That has helped A LOT and he is no longer stuffy at night. Saline drops are good to use if he will tolerate them. I also put vicks vapo rub on his pj's (as it isn't good to use it on the skin under 2 years) which helps a lot too. Just my two cents!