Princess Diana was also playful on top of being an elegant, poised woman.

David Butler recently shared a never-before-seen image of the late Princess of Wales using her nickname to sign a Christmas card. "Wishing you a very Happy Christmas and New Year and lots of love from the four of us, Duch and Charles," Princess Diana wrote.

Butler found Princess Diana's choice of nicknames to be interesting. "Very unusual to see Diana use her nickname on a christmas card!" Butler wrote (via Express).

The publication noted that "duch" was a childhood nickname for the People's Princess. Her family and friends called her by that name. The name stuck and was revealed in the 2005 book "Diana Princess of Wales" by Beatrice Gormley.

"Diana was usually friendly and good-natured, but not when she was called Di. 'Say that again', she told her schoolmates, 'and you die. I am Duchess. Duch,'" Princess Diana reportedly said.

"Later in the year, Diana took part of a Dutch doll in the school play. She was too shy to speak in front of an audience, but the Dutch doll wasn't supposed to say anything," Gormley wrote. "When it was her turn, Diana moved around the stage with stiff movements just like a doll and everyone clapped for her. Now the nickname Duch seemed to fit her even better."

In related news, on Aug. 31, the royal family commemorated the 21st anniversary of Princess Diana's death.

According to Judi James, a body language expert, Prince William and Prince Harry's mother was "unhappy" and "hunted" hours before the tragic accident that killed her.

"There is a huge difference to Diana's responses in the Ritz photos to her normally upbeat and stoic attitude to the paparrazi interest in the past," James told Daily Star. "She might have (usually) ducked her head and smiled indulgently at the same time. (But) she does look more hunted and less in control here and her intense shielding gestures and unhappy facial expression could suggest some new levels of fear."

The firefighter who responded to the tunnel thought that Princess Diana would survive the car crash. According to him, the royal was in better shape compared to the other passengers and there was no blood in her. In fact, she was still conscious. Unfortunately, Princess Diana died in the hospital.

Princess Diana
Princess Diana used her childhood nickname to sign a Christmas card. Pictured: Princess Diana at Red Cross headquarters in Washington DC on June 17, 1997. Getty Images/Jamal A. Wilson