I feel you are definitely on the right track. Another thing you might want to check into is food allergies . My son was allergic to wheat and milk and when we took these out of his diet it really helped his sinus/asthma problems. Took us forever to figure out he was even allergic to them though. We used oregano oil on my son with his sinus and asthma problems and it REALLY helped. We bought both the gelcaps for internal use and the drops for under the tongue. It's tough because those drops are nasty and warm. We actually added a bit more oil to them because they are so nasty tasting but it really improved him immensely. We bought the drops and the gel caps of oregaresp by North American Herb and Spice co. They are a little better tasting that just the oregano itself. The Oregaresp is made for sinus and bronchial problems specifically, but it has a little better of a spicier taste. My son still doesn't like it but it really helped him. There is a very good book out there called The Respiratory Solution by Cass Ingram on the subject of oregano oil and sinus infections, asthma, breathing problems and a whole plethora of other illnesses. See if your library has a copy and if not, have them inter library loan one in for you from another library. There is also another sinus spray made with grapefruit seed extract that you can get for sinus problems made by Nutribiotic. Good luck to you and your daughter!