A little bit of honey, too sooth the throat (Although unsure when kids are ment to have honey.
Vaporiser in her room
close the house up early to keeo it warm
sock on her feet
if it gets into a coughing fit - go into a steamed bathroom (Only a few mins at a time)
Plenty of fluids
euky bear rub on the chest and feet
raise the head of her bed

Ummm - Thats all i have...

One more thing, If the cough has been lingering for a while, I would get it checked out by the Doctor, HTH!