"Friend and wonderful godmother", Princess Diana's friend wrote for her.

On the 21st anniversary of the death of Princess Diana, one of her friends shared a rare candid picture of the royal.

One of Diana's close friends, Rosa Monckton on August 31 took to Twitter to share a picture where the royal is seen laughing her heart out. She can be seen sitting inside an aeroplane wearing a casual outfit.

"Diana as I remember her. Not enough is written about her sense of fun and zest for life. Friend and wonderful godmother to Domenica. RIP," she tweeted.

Ms Monckton, who got introduced to the royal through a mutual friend, said the former loved her dearly.

Diana as I remember her. Not enough is written about her sense of fun and zest for life. Friend and wonderful godmother to Domenica. RIP pic.twitter.com/WP49dNDeEu - Rosa Monckton (@MoncktonR) August 31, 2018

People magazine reported that Ms Monckton had even named Diana the godmother of her daughter, Domenica, who was born with Down syndrome.

Ms Monckton even thanked the royal for giving her the courage to fight Domenica's disease right from the time of her birth.

On August 31, 1997, Diana died in a car crash in Paris.