"She is Lyanna’a daughter. She developed a disease that caused blindness at birth. With the help of the couple of alchemists who sheltered her mother years ago, she was cured. No one really knows how they managed to cure her, but the rumor spread that her mother practiced black magic and that the loss of her father and husband had driven her mad."

Lineagedos Lore

You can find Minerva in Dion: