Wild Swans, by Xanthe Gresham Knight & Charlotte Gastaut

A retelling of the Grimm/Andersen fairy tale in which a magical stepmother-queen transforms Eliza's eleven brothers into swans as plague ravages their kingdom. After the queen and king die, Eliza sets off to break the spell, knitting enchanted shirts for her brothers while working to end the plague, facing suspicious villagers along the way. Reviewers highlight Eliza as "a brave and focused heroine" who ultimately claims the throne herself rather than marrying into power.