My DS 3.25, has had a cold on and off all winter, (like most kids), Whenever he wakes up with a blocked nose he cried out for me. I tried Karvol, Vicks etc, they made him better but he still continued to wake up. However a few days ago I bought from boots a VIVA breathe clearly plug in vaporiser. Its cost £5 something and you have to buy refill pads which work out about 50p a night, but just wanted to let people know that for the past 2 night even though he has been full of cold, he slept well and didn't wake up. Even woke up in the morning unblocked. Hope this helps anyone.