"Copyright 1949 by Scott, Foresman and Company, Glenview, Illinois"--Title page verso.
Sequel to: The Boxcar children.
Summary
Summer vacation on an almost private island gives the Aldens a challenge. Henry, Jessie, Violet and Benny used to live alone in a boxcar. Now they have a home with their grandfather and are spending the summer on their own private island. There is a mysterious stranger on the island with a secret--but that's not the only surprise in store for the Boxcar Children.