PRINCE William has told of his sense of "emptiness" since the death of his mother, Princess Diana.
William, 26, said the loss of a loved one was "one of the hardest experiences" to endure and told of his sadness at never again being able to say the word "mummy".
Diana died in a 1997 car crash in Paris alongside boyfriend Dodi Fayed. An inquest last year returned a verdict of unlawful killing, blaming the chauffeur's driving and pursuing paparazzi photographers.
The future king's comments today came as he became patron of The Child Bereavement Charity, which Diana supported, ahead of its launch of a Mother's Day campaign.
"Losing a close family member is one of the hardest experiences that anyone can ever endure," he said.
"Never being able to say the word 'mummy' again in your life sounds like a small thing.
"However, for many, including me, it's now really just a word - hollow and evoking only memories.
* Reader's Comments: William sad he'll never say 'mummy' againNEWS.com.au,
* Good riddance, Yummy MummyCourier Mail, 16 Feb 2009
* Engaging fare loaded with sexual tensionThe Australian, 31 Jan 2009
* All mysteries great and smallThe Australian, 24 Jan 2009
* Hamas' TV diet of hatredDaily Telegraph, 8 Jan 2009
Oh God, how I understand his meaning. My father died when I was just 3, my own Mummy at 13, my brother at 19. I'm now 38. My life moves forward; I have my own family, a business...
Kate of Perth
"I can therefore wholeheartedly relate to the Mother's Day campaign as I too have felt - and still feel - the emptiness on such a day as Mother's Day."
The charity campaign will ask people to remember how hard the date can be for children who have lost mothers, or mothers who have lost children.
William, who is second in line to the throne after Prince Charles, is training to become a search and rescue helicopter pilot in Britain's Royal Air Force.
Media speculation is growing that he could announce his engagement to long-term girlfriend Kate Middleton, who he met while studying at Saint Andrews University in Scotland.
Mother's Day in Britain is marked on March 22.