Ethlin

“And I know you, Sigurd. You are always jumping into this kind of stuff without thinking. Especially with Father being away... I knew I had to come.”
— Ethlyn, to Sigurd

Ethlyn (Japanese: エスリン Ethlin) was a member of the Chalphy nobility of Grannvale, and the wife of Prince Quan of Leonster. She was an ally of her elder brother, Sigurd of Chalphy, in his battles with Verdane and Agustria and after he was deemed a traitor. Her children, Altena and Leif, would later play pivotal roles in assisting Sigurd's son Seliph in his liberation war against the Grannvale Empire.

(Source: Fire Emblem Wiki)