With increasing regularity, William and Harry are making reference to Princess Diana as they praise her inspiration

By Simon Perry
Updated October 16, 2015 03:40 PM
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Prince Harry‘s heartbreaking card addressed to “Mummy” on her coffin as he and brother Prince William walked in Princess Diana‘s funeral procession was a very visual sign of how much they were grieving.

Since her passing 18 years ago, there’s not been a day when both princes haven t thought about her, and they have periodically spoken about her in public.

Now, in the last two weeks, both of her sons have invoked her memory. When Harry, 31, was joining wounded veterans on their 1,000 mile walk around Britain, he said Diana was the inspiration behind their charity work, while William spoke on Thursday about how “grief is the most painful experience that any child or parent can endure,” at a gala event for a charity both he and his mother backed.

Experts detect that the princes feel bolder and have more opportunity to keep Diana’s memory and legacy alive.

The Daily Mirror‘s royal correspondent Victoria Murphy, who spoke with Harry on his Walking with the Wounded tour earlier this month, tells PEOPLE, “He brought up the subject of his mother and how he and William were keen to follow in her footsteps making visits behind the scenes with charities.

“In some ways I was a little surprised he chose to mention her as we were just talking generally about his work, but I think it shows just how strong an influence she continues to be on him and on how he carries out his work.”

Harry spoke about her as he set up his African charity Sentebale more than 10 years ago, and made an emotional address at her 10th anniversary memorial service.

More recently, William has given his wife Kate Diana’s engagement ring and the couple partly-named Princess Charlotte after her late grandmother.

Ingrid Seward, editor-in-chief of Majesty magazine, and author of books on the princes, says, “Now, they feel the confidence to talk about it without feeling uncomfortable. It took awhile, but it doesn t mean that they weren t thinking about it. It’s just they have the confidence and want to speak about it.

“For anyone who is grieving, talking publicly about someone is the way of keeping a parent alive, so they are with you.”

Some of it is opportunity. Bestselling author Judy Wade, who covered Diana’s life and has followed the princes since they were born, tells PEOPLE, “They have more ability to talk about it. They are more central and they can be listened to. They are doing it more and more because it needs to be done. Anyone who knew Diana wouldn’t want her to be forgotten. She was the most dazzling woman in the royal family ever.

“There’s a whole generation who never knew about her. It is a wonderful thing that they are doing because she was undoubtedly the outstanding royal figure of the last century. She deserves to be remembered.”

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