my sons legs really improved on the front when he started walking!
dustmite allergy is one of his highest allergens.
so we have melted some credit cards over the years.
no hanging washing on line, ( tree pollen, hay fever) for some years.
all clothes tumbled dried, never hung on rads.
damp dusting, leather furniture, frozen teddies over night, then washed the next day.
boil washing bedding.
books , toys in plastic boxes, wooden flooring in bedroom , and most of house.
and good quality allergy bedding.
all total nightmare, but did work for some years.
now at 13 on daily antihistmine as dustmite/tree pollen/dog etc very very high , causing mild allergic reactions in morning.
cant offer much more advice than you have already been given, but can say, been there got the t-shirt. ( p.s did get some decent sleep by time he was 2 -2 1/2)