Children should be exposed to eggs, peanuts etc early, mine were and have had adverse effects.
Keep dogs and cats in the house, exposure early is the best bet for not developing allergies.(There are exceptions)
Don't vacuum and dust too much.
I got allergy shots from age 7-14 It worked, I was one of the lucky one's. They don't do that anymore as far as I know the treatment I received cured me todays don't.
They still do allergy shots, and there are some other treatments.