The other daughter : [a novel]
(Book)

Raised in a poor yet genteel household, Rachel Woodley is working in France as a governess when she receives news that her mother has died, suddenly. Grief-stricken, she returns to the small town in England where she was raised to clear out the cottage...and finds a cutting from a London society magazine, with a photograph of her supposedly deceased father dated all of three month before. He's an earl, respected and influential, and he is standing with another daughter-his legitimate daughter. Which makes Rachel...not legitimate. Everything she thought she knew about herself and her past-even her very name-is a lie. Still reeling from the death of her mother, and furious at this betrayal, Rachel sets herself up in London under a new identity. There she insinuates herself into the party-going crowd of Bright Young Things, with a steely determination to unveil her father's perfidy and bring his-and her half-sister's-charmed world crashing down. Very soon, however, Rachel faces two unexpected snags: she finds she genuinely likes her half-sister, Olivia, whose situation isn't as simple it appears; and she might just be falling for her sister's fiancé...