Mystery at Shadow Pond by Mary C. Jane, 6th Scholastic paperback printing, TX318, 1965, 124 pages. Illustrated by Ray Abel. Cover illustrated by Dom Lupo.
DESCRIPTION:“Why were Grampa’s letters so important to old miserly Mr. Willey, to the strangers in the flashy red car, and to the writer at Shadow Pond Park?
Margie and her brother, Neale, know that the mysterious letters may help save their beach and field- and most important, their beloved horse. But the letters are gone! Who could have taken them? And why?