Brief Answer:
Conjunctivitis.

Detailed Answer:
Hi,
Thanks for asking the query.

Your kid is having conjunctivitis.A red eye is one of the first and most common symptoms of conjunctivitis. Conjunctivitis is the inflammation of the tissue that lies over the white part of the eye and lines the inner side of the eyelid. It is usually the result of a viral infection and can easily spread from one person to another. An eye examination and testing a sample of the fluid secreted by the eye can be used to diagnose conjunctivitis.
Test suggested-
Swab culture from eye.

I would suggest the following treatment in this case:
Eye drop Moxifloxacin kid 2 drops twice daily.
Syrup cefixime 5ml twice daily
Syrup cetrizine 2.5 ml once daily.
Wash his eyes from chilled water three times a day.
Don't let him rub his eyes again and again.

Please discuss this treatment option with your local doctor.

It will take 3-5 days to settle down.

Thanks.

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