Letters written by Princess Diana to a former steward at Buckingham Palace are being sold at auction in Cambridge.
The correspondence is said to give insights into the life of the royal family at around the time Prince William and Prince Harry were children.
Auctioneers at Cheffins have valued the letters at £15,000.
An exhibition devoted to Princess Diana will close next year at her family home where it has been held since 1998.
Her wedding dress is among 150 personal items on show each summer.
The display has raised £1.2 million for charity since it opened at Althorp House, Northamptonshire, the year after Diana, 36, died in a Paris car crash.