Her Sister's Secrets — V.J. Chambers

An anonymous letter summons Emilia Farrow to Siesta Key. An oceanfront house has been rented there for her, its closet stocked with designer clothes in her size. The mysterious correspondent promises that if she comes, she will find out what really happened to her sister Violet.

Her death wasn't an accident.

Immersing herself in a world of wealth and privilege, Emilia has nightmares about the Wainwright mansion next door. Her mother used to work there years ago. Recently, her sister also worked for the Wainwrights. Just looking at the house makes Emilia feel as if she can't breathe. Her strongest memory of the place is her mother packing up her and her sister and fleeing in the hours before dawn.

What happened all those years ago? Was Violet murdered? Who killed her? And who rented this house for Emilia?