Hi,thanks for query.This does not seems to impetigo
,either this is a viral infection or some allergy
.Viral is more likely as you said your neighbour`s daughter is also having same.Please do not worry,in most of the cases they are self limiting.Give him anti allergic medicines for itching if he has,give him more of fluids and symptomatic treatment as per need.You can apply lacto calamine
over it.It should go withing couple of days,if not please consult your primary care
wishing him good health.