The Star Of Kazan by Eva Ibbotson

A spirited orphan named Annika is raised with warmth and practical wisdom by a loving, working-class family until a stranger arrives claiming she is the long-lost heir to a wealthy household; swept away into a life of comfort and cold formalities, she must confront loneliness, unravel the truth of her past, and—helped by loyal friends and her own common sense—decide where she truly belongs, in a gentle tale about identity, belonging, and the meaning of family.

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