Trixie Belden #3 - The Gatehouse Mystery - 1951
Jim Frayne is now officially Honey's new brother because her parents decided to adopt him. And Honey couldn't be happier; she always wanted a sibling. Jim now lives on the Wheeler estate, but he still has his own money in trust account, thanks to the fortune of his great-uncle.
The Gatehouse Mystery focuses on a mysterious new chauffeur hired by the Wheeler family. But Trixie thinks there is something funny going on with this man and she just doesn't trust him. Someone has been sneaking into the gatehouse behind the Wheeler estate and Trixie is determined to find out who. Trixie and Honey have also found a diamond, which Honey says does not belong to either of her parents.
This book is the first time we get a hint of the Bob-White Club that will be formed. The Bob-Whites include Trixie and Honey, as well as Jim and Trixie's older brothers, Brian and Mart.