The Shell Secret - Sue Palmer

For eleven-year-old budding detective Alice Clark, summers in Trevellen used to mean roaming the beaches and rockpools, collecting shells with her sister, Poppy. But this year is different. A year after Poppy's death, Alice returns alone - determined to build a shell memorial in her honour, and desperate to ensure her sister is never, ever forgotten. A gripping mystery set on the Cornish coast.