Santa Barbara, California - In the Prince Harry has described the heartbreaking grief he experienced following the death of his mother Diana.

The 36-year-old contributed the foreword to a children's book dealing with loss.

"When I was a young boy I lost my mum. At the time I didn't want to believe it or accept it, and it left a huge hole inside of me," Harry wrote in the newly released Hospital by the Hill.

Princess Diana died in a Paris car accident in 1997. She was being chased by paparazzi at the time. Harry has recently mentioned the fear of "history repeating itself" with the media treatment of his wife, Meghan Markle, in explaining why the Sussexes have separated from the royal family.

"We all cope with loss in a different way, but when a parent goes to heaven, I was told their spirit, their love and the memories of them do not. They are always with you and you can hold onto them forever. I find this to be true," he also said.

The children's book, a collaboration between author Chris Connaughton and illustrator Fay Troote, tells the story of a child whose mother treats Covid patients in a hospital and later dies herself.

It is aimed at children who have had similar experiences.