Brief Answer:
Most likely infection of eye (blepharitis)

Detailed Answer:
Hello

Thanks for the query

I can understand your concern.I have seen the image.There is swelling of left eye especially below the lower eye lid with some inflammation of lower eye lid(blepharitis).
Presence of discharge also goes in favour of blepharitis.
I would suggest you to put some antibiotic drop like azithromycin three to four times a day for 5-7 days.
Clean the eye after proper hand wash with help of soaked sterile cotton swab from inside out.
Do this once then through the swab (don't use it again).Do it three to four times each 4-5 times a day.

If redness or swelling increases rapidly consult an ophthalmologist for clinical evaluation and management accordingly.

I hope this helps.
Please let me know if you have any more query.
Wishing for your child's speedy recovery.
Regards

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