Hello Welcome to health care magic. I reviewed your history. It seems from the history that your sister is suffering from glaucoma. Since she has lost vision in one eye she needs to be under appropriate treatment for glaucoma to prevent vision loss in the eye. The treatment options are anti glaucoma drugs, laser and surgery. The treatment needs to be due aided based on the investigations like visual fields, optic disc damage and intraocular pressure. Hence I advice you to consult your ophthalmologist or preferably a glaucoma specialist for examination and treatment accordingly. Hope this information is helpful to you. Thank you With regards