#12 Sister by Rosamund Lupton

Quote
Nothing can break the bond between sisters ...When Beatrice gets a frantic call in the middle of Sunday lunch to say that her younger sister, Tess, is missing, she boards the first flight home to London. But as she learns about the circumstances surrounding her sister's disappearance, she is stunned to discover how little she actually knows of her sister's life

Interesting mystery. Some of the logic, especially when it came to medical stuff, was flawed. The writer employs an interesting device to tell the story. It was entertaining but I wouldn't rank it as high as "Gone Girl" (as some reviewers have).

Joan