how old is she ? children from 1 - 7 years suffer from this problem because they donot have a well developed immune systm ..slightest infection can affect the airway and lungs which leads to cough and wheezing ... her immune system will become stronger with growing age and probably she'll have lesser episodes of allergies thn ..
for cough put few pillows under her head and shoulders while sleeping so that she can sleep in a slightly upright position and it'll allow her to breathe easily as well ...
give her a warm bath daily and keep her indoor as much as possible ...identify food allergy if any and avoid those foods ..make sure she is well hydrated and is drinking alot of fluids
and give her 1 tablespoon of honey with a pinch of turmeric on rising in the morning and before going to bed atleast for a month .. or mix a pinch of turmeric in a cup of warm milk and make her drink regularly .. tht'll help too and if allergies and wheezing is distressing, you should consult a doctor..