The Duke of Sussex has reflected on the pain of his mother’s death in a foreword to a book for children of health workers who have died in the coronavirus pandemic.

Prince Harry wrote that the death of Diana, Princess of Wales in 1997 when he was 12 had left “a huge hole inside of me” but that it was eventually filled with “love and support”, according to the Times.

The book, Hospital By the Hill, tells the story of a young person whose mother dies while working on the frontline at a hospital during the Covid crisis.

Written by Chris Connaughton and illustrated by Fay Troote, the book is being given to similarly bereaved children as part of the National Day of Reflection next week, a government initiative to mark the anniversary of the start of lockdown in the UK.

“If you are reading this book, it’s because you’ve lost your parent or a loved one, and while I wish I was able to hug you right now, I hope this story is able to provide you comfort in knowing that you’re not alone,” the duke writes.

“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. I know how you feel, and I want to assure you that over time that hole will be filled with so much love and support.”

Harry wrote that he had found that while a lost loved one may be gone forever, they are “always with you and you can hold on to them for ever”.

“You may feel alone, you may feel sad, you may feel angry, you may feel bad. This feeling will pass. And I will make a promise to you – you will feel better and stronger once you are ready to talk about how it makes you feel.”