Well, generally speaking, you will not get an eye stye from your sister. As we know that a stye is inflammation of the eyelid, usually inside one of the small glands lining the eyelid. Most styes are caused by infection from bacteria. But you should know that they are not contagious, in the sense that you don't "catch" a stye from someone who has one. Styes form as part of a more complicated process than simple contact, and the body's natural defenses tend to block stye formation. And to avoid getting a stye, or transmitting bacteria to another person if you have one, you should pay more attention to regular hand hygiene.
