In 1970, three-year-old Cheryl Grimmer went to Fairy Meadow beach, Australia with her parents and her seven-year-old brother Ricki. She never returned home.
Cheryl was taken from the changing rooms at the top of beach but no-one knows what happened.
Her brother Ricki has been searching for her all his life.
Now, the BBC Fairy Meadow podcast is investigating the case. Fifty years on – can the mystery be solved?
Correspondent: Jon Kay, Filmed and edited by: Andy Alcroft, Music: Elizabeth Purnell
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