Prince William Shares Emotional Tribute to Princess Diana: Grief Is the 'Most Painful Experience'

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Prince William is still mourning the loss of his mother, the late Princess Diana.

In a touching speech on Thursday night at the 21st anniversary of the charity Child Bereavement U.K. gala in London, the 33-year-old royal opened up about feeling the loss of his beloved mother. Princess Diana died in a car accident in 1997, when William was 15 years old.

"My mother was determined to help those in need and she would have been immensely proud -- as I am -- of all that Child Bereavement U.K. has achieved these last 21 years," William said of the charity she helped launch in 1994, which supports families and educates professionals when a baby or child dies, or is dying.

"What my mother recognized back then -- and what I understand now -- is that grief is the most painful experience that any child or parent can endure," he added. "As a father to two young children myself, I now appreciate it all the more."

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William said that he was honored to continue his mother's legacy.

"I was honored to be invited to become patron of Child Bereavement U.K. [six years ago] to continue my mother's commitment to a charity which is very dear to me," he said. "CBUK works with military families, with the wrecked families of suicide victims, with little children whose lives are torn apart by the inexplicable death of a parent. And yet amid all this misery, CBUK -- and I don't know how they do this -- brings warmth, comfort, a guiding hand, a way through, even color and joyfulness, and a renewed opportunity for love as a family reknits itself after tragedy."

On Thursday, Kensington Palace tweeted a photo of Princess Diana at the launch of the Child Bereavement Charity 21 years ago.

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These days, Prince William has a beautiful family of his own. In July, he gushed about his wife, Kate Middleton, as well as their adorable children, 2-year-old Prince George and 5-month-old Princess Charlotte.

"Catherine has been doing an amazing job as a mother, and I'm very proud of her," William told reporters. "[Princess Charlotte is] a little joy of heaven, but at the same time, it is more responsibility, looking after two little ones, especially when George is around. He's a little monkey."

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