My 4yr old daughter has had a cough for 6 months, sounds phlegmy but nothing comes up, makes her sick she has asthma apparently although never wheezes . Have tried dust mite covers on her bed, steroids, antihistamenes and none have worked. she also has a permanantly runny nose and snores. Doctor doesn t seem to believe me and it is quite upsetting to see your child be in pain and no one helping! It is affecting her sleep, she gets on average 3-4hrs per night and it is affecting her at pre school. Help, please!