Caitriona Palmer had a happy childhood, raised by loving adoptive parents. In her late twenties, she located her birth mother, Sarah, and they developed a strong attachment. But Sarah set one painful condition to this joyous new relationship: she wished to keep it secret, from everyone. Who was Sarah, and why did she want to preserve a decades-old secret? This is the story of Caitriona's quest to answer these questions, and of the intense, furtive "affair" she and her mother conducted. It is a searing portrait of the social and familial forces that left Sarah—and many other unwed Irish mothers of her generation—frightened, traumatized, and bereft. It is also a beautiful account of a remarkable relationship.