Grace -
If your nephew is having breathing problems, seriously consider food allergies, or dust mites in pillows/bedding and carpet. Toss the pillow if it is more than 2 years old, buy a new one along with a dust mite cover.

Get a mattress dust mite cover as well.
A highly effective product to relieve those of allergies is Sterol 117. You can read about it here -
http://www.healthegoods.com/product/sterol-117-biogenesis/natural-health-supplements
If your nephew can swallow pills, take 2 capsules first thing in the morning away from meals--about 20 minutes. And take 2 at night right before bed--again away from meals/milk products. After 1 week drop the dose down to 1 capsule AM and PM.
If your nephew cannot swallow pills, open the capsule and put the powder in a spoonful of applesauce. Give as suggested above.
In health,

Dr Ben