A photo of a teenage Diana Spencer that's marked "not to be published" will be featured in an auction this month in New Hampshire.
RR Auction says the photograph might never have been seen publicly until now.
The photo stamped February 1981 on the back shows Diana with a young friend seated beside her. It was taken around the time Charles, the Prince of Wales, and Lady Diana Spencer ended months of speculation with the announcement they were engaged. They were married on July 29, 1981.
The photo comes from the Caren Archive, a private collection of rare newspapers and other publications, and was purchased seven years ago from the Daily Mirror newspaper.