Thanks for consulting at Healthcare Magic. Chronic nasal congestion in kids commonly occurs due to infections, allergies, irritants, enlarged adenoids etc. Chronic nasal congestion causes blockage of eustachian tube which causes ear problems. Clear watery nasal discharge, rashes, sneezing may suggest some allergic cause. Sticky, yellowish nasal discharge, post nasal drip, fever may suggest infection (sinusitis). As you have already completed courses of antibiotics, I would suggest you avoid exposure to possible allergens, use nasal decongestants and oral antihistaminics and arrange consultation with ENT specialist. He will do detailed clinical examination of nose, nasopharynx, throat and ear to determine the exact cause.