Sandy is mentioned in the below article about Mark Goddard (RIP) and their publicity date when they attended the premiere of “But Not for Me” in October 1959.
Meet the girl who started it all, Kathy Kohner-Zuckerman! Her father, Frederick Kohner, wrote Gidget: The Little Girl with Big Ideas, about his daughter’s surfing and beach adventures in Malibu. The 1957 book was the inspiration for the 1959 movie starring Sandy, subsequent films in ‘61 and ‘63, and later on the TV show in 1965.