Eloise Bridgerton’s distinctive eye condition, known as heterochromia, is a rare genetic trait that causes her one eye to be lighter in color than the other. In her case, her left eye is a pale blue, while her right eye is a rich brown. This condition is often considered a cosmetic anomaly, and while it can sometimes indicate an underlying health issue, in Eloise’s case, it is purely a physical characteristic that adds to her unique and alluring appearance.