hi i had gone through your query and understand your concerns. i would come up with the possibility of ALLERGIC DERMATITIS
may be the cause for her sufferings.
-insect bite is one of the triggering factor for her allergic reaction
are other possible causes.
i advise you taking Homeopathic
medicines gives safe and permanent cure for her allergic dermatitis complaints
consult your local homeopathic physician for correct diagnosis of the case and remedy to fit her complaints
I hope this is helpful for you, thank you