Blue Bay Mystery Gertrude Chandler Warner (Boxcar Children, Good, 1993, HC, 158 pages, Albert Whitman & Co.)

Former library book in good condition: cover has some wear; pages have some wear; typical library stickers/stamps. ISBN 0807507938

The Boxcar Children are on a trip with Grandfather to a beautiful island in the South Seas! The island is supposed to be deserted, but as the Aldens explore, they start to find signs that suggest they are not alone. Is there a castaway living somewhere on the island?