The Case of the Peculiar Pink Fan by Nancy Springer (Enola Holmes) Book 4

When Enola Holmes encounters her friend Lady Cecily hiding behind a pink fan, she finds it peculiar. Cecily is being held hostage in an abysmal orphanage, forced into a miserable marriage. Enola joins forces with the much older famous brother Sherlock who she has fought desperately to elude, and risks her own freedom to rescue her friend. The Enola Holmes Mysteries is a young adult fiction series of detective novels by American author Nancy Springer, starring Enola Holmes as the 14-year-old sister of an already famous Sherlock Holmes, twenty years her senior. There are nine books in the series, and one short story all written from 2006–2023. Book published in 2008