I don't know if this applies to kids. But I used to get a dry cough and normally didnt think anything abt it. But one winter it just got so ridiculous that I eventually went to the dr. The dr actually gave me an inhaler, not the asthma one. Basically I had some form of allergy like hayfever bordeline being asthmatic. I'm not trying to scare you or make it sound serious. Just thought maybe a different perspective. Hope she feels better.