I think it's an infection to the eyelids because of blocked "pores" of the eyelids. Oh my, your sister's sty wasn't an ordinary one, I think.

Yes my mother also have the same problem from 3 months. After that I contact to doctor and he give me a some medicine and they really works. So you can also contact to your doctor.....

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Anti Aging | Skin Care

Boil 1 teaspoon of coriander seeds with a cupful of water like an herbal tea preparation to wash the eyes 3-4 times a day.

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GHD Repairs-http://www.fixmyghds.com