My brother had a stye in his eye for the longest time. When it went away, it would return in just a couple of weeks again. He finally went to the doctor. He is the time of person who doesn't like using prescriptions, like me. The doctor suggested to use "Johnson n Johnson Baby Shampoo". This shampoo says right on the bottle that it is as mild as water in the eyes. The doctor said to use this as well as warm water and a wash rag. Sure enough, it cleared his eye right up. I'm not sure if you are looking for something completely natural, or if you are just looking to avoid getting a prescription. Good luck! Be sure she doesn't touch her eye with dirty hands!