That's strange because I baby doesn't suffer hayfever until the older from 13 or 14yrs it's too early
Use vaseline inside his nostrils it traps pollen from entering
Second what Hannah said defo get an air filter it can help loads. Try wiping his hands nose and eyes with a wet flannel often if he’ll let you. Hope it starts to ease up x
Get an air filter for his bedroom and/or your living room. It sucks pollen, dust, allergens, pollution and virus out of the air. We have them for my husband and it helps a lot. We use Smart Air. Hope you find something that works for you x