There have always been rumors swirling around the Summerbourne twins, Seraphine and Danny. Their mother died just days after their birth, having fallen off a cliff on the estate. And now that they are adults, Danny has put the rumors and questions about his family behind him, but his sister is not so certain. Seraphine still has doubts about what happened the summer that they were born. And when they lose their father in a devastating accident, she feels like she just has to know more about where she came from.

Looking through old mementos, Seraphine finds a couple of clues to offer her some direction. One is a photo of her mother holding one of the twins shortly after their birth. But which one is it? And the other is an information sheet about the summer nanny her parents hired that summer to look after their older brother Edwin.

A handful of internet searches brings Seraphine to Laura, the au pair from that summer. But Laura doesn’t want to talk, her grandmother and brothers are against her attempts to find the truth, and Seraphine finds her courage flagging. But as always, the truth finds its way to the light, dispelling the rumors and half-truths that kept the siblings in the dark about who they are and where they came from.

Told in alternating times, from the summer of the twins’ birth as well as Seraphine’s present-day search to find the truth, The Au Pair by Emma Rous is a delightful, twisty, slowly unfolding mystery that balances an array of human emotion with a creepy underlying uncertainty. At the end of the day, this lovely novel is about relationships and how they affect us. It’s beautifully written, a fascinating mystery, and a satisfying story of family, both the family that comes from blood and the one that comes from choices. I loved The Au Pair, and I recommend it to all readers of thrillers, mysteries, and literary fiction about family relationships.

Galleys for The Au Pair were provided by Berkley, with many thanks.