GEN: forgotten book title

["Jacqueline A. C. Keith" <jkeith@PEN.K12.VA.US>]

I've been asked to try to find the title of a book, probably
written 1950-70, that was the fav. of a parent at my school.
As far as I can understand, it was about a brother and a
sister, ages 10-12, who are stuck on a deserted island and
hunting for a treasure.  There may be bad guys or pirates on
the other side of the island also looking for the treasure.
Any ideas?--Thanks.

-
Jackie Keith, Librarian                                 jkeith@pen.k12.va.us
Battlefield Middle School      11120 Leavells Road, Fredericksburg, VA 22407
Battlefield's Home Page: 
http://www.spotsylvania.k12.va.us/middle/battlem/battmid.htm

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