Allergic conjunctivitis: This is a common condition in children, often presenting with itching, redness, and discharge. The age of the child and the presence of eye irritation make this a likely diagnosis, especially if there's a history of allergies or exposure to allergens.

Viral conjunctivitis: This is highly contagious and common in children, characterized by redness, itching, and a watery discharge. It often accompanies a viral upper respiratory infection.
Blepharitis: Inflammation of the eyelids can cause irritation, redness, and sometimes a sticky discharge. It's common in children and can be associated with poor eyelid hygiene or conditions like eczema.
Foreign body: Given the age of the child, it's possible for small objects to accidentally enter the eye, causing irritation and discomfort.

Gonococcal conjunctivitis: Although less common, this condition is serious and can lead to blindness if not treated promptly. It's particularly concerning in children and requires immediate medical attention.
Herpes simplex keratitis: This viral infection can cause severe eye pain, redness, and sensitivity to light. It's crucial to diagnose and treat early to prevent complications.
Chemical burn: Exposure to chemicals can cause severe eye irritation and potentially lead to long-term vision problems. Immediate flushing of the eye and medical evaluation are necessary.

Kawasaki disease: This condition can present with conjunctival injection among other symptoms like fever, rash, and lymphadenopathy. It's rare but important to consider due to its potential for cardiac complications.
Juvenile idiopathic arthritis (JIA) associated uveitis: This is a rare condition that can cause eye inflammation and irritation. It's associated with JIA and requires prompt treatment to prevent vision loss.