Mystery Behind the Wall — Gertrude Chandler Warner

One warm night four children stood in front of a bakery. No one knew them. No one knew where they had come from.

Henry, Jessie, Violet, and Lenny used to live alone in a boxcar. Now they have a home with their grandfather -- and have a mystery to solve under their own roof.

When the Boxcar Children find an old journal behind the closet wall in the guest room, they never dream it will lead them on a search for a valuable coin collection. What happened to the girl who wrote the journal...and what is she trying to tell them...?