We just got a Siberian kitten a little while ago - I am EXTREMELY allergic to cats. I can enter a room and tell you own a cat without ever seeing one. I will get hives, sneezing, watery eyes, just absolutely miserable. I'd say my allergies are way better with our Siberian. Hypo-Allergenic means LOWER allergy, not NO Allergy - this breed has a lower amount of a protein in their saliva called Fel D1(cats lick their fur, the fur sheds after this protein dries on it, and gets into the air, creating dander which is what people are allergic to) - If your cat is spayed or neutered, it also helps lower the allergen. I'd say your son will be okay. BUT it depends from person to person. He'll probably build quite a bit of immunity over the next few weeks to that one cat. He won't be able to around ALL cats, but he'll be able to tolerate the one that he's around all the time. Make sure you have a HEPA filter, and vacuum your home/wipe down surfaces at least once a week. Also make sure your son washes his hands after playing the cat, and teach him not to touch his face after petting the cat. This will probably lessen his allergies until he possibly builds immunity. Good luck!