A Beautiful Family: A Novel by Jennifer Trevelyan

At ten years old, she catches more than her parents and older sister suspect. Over their summer break, her mother plans to finish her novel, her father wants to grill and watch cricket, and her fifteen-year-old sister hopes to catch the eye of a local lifeguard. With everyone around her distracted, she teams up with a new friend to solve a mystery that haunts this vacation community: they'll close the case of what happened to Charlotte, a child who was presumed drowned two years earlier.

But things aren't quite as they seem, and as the children look for clues, they inadvertently dislodge information they wish they'd never uncovered. Are her parents happy together? Is her sister putting her trust in the wrong people? Is their vacation rental as safe as it seems? And when someone else goes missing, the family find themselves at the center of an urgent police investigation.