help!

kasey
Alright, so little one has had this nasty wet cough off and on for the last 3-4 weeks. 
Keeping her up throughout the night. We have a cool mister going at night! Also, she sits in a steamy bathroom! But does no justice! 
We took her to the doctors 2 weeks ago and he said that unfortunately it was just a normal old cold that had to play its game. I just feel as if 4 weeks with a nasty wet cough that keeps her up all night long is more then just a game that needs to be played. 
Anyone have any suggestion on what I can do because doc said that there nothing for her to take.