Boston-based RR Auction says the dark blue cotton-polyester sweatshirt that was a gift from airline founder Richard Branson is expected to get more than $5,000 during the online auction.
The garment features the airline's 'flying lady' logo with the words "Fly Atlantic" in white.
It is being sold by Jenni Rivett, Diana's longtime personal trainer. Diana gave Rivett several sweatshirts months before her August 1997 death.
In a letter that comes with the shirt, Rivett writes that Diana thought there were more pressing issues in the world to worry about, so wearing the same thing to every session would be "a good way to stop the media frenzy."
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