Charles Spencer Says William and Harry Find Tranquility At Diana's Grave 

Princess Diana’s brother is reflecting on his “final duty” to his sister.

The late princess is buried on the island of the Oval Lake at the family estate of Althorp, around 75 miles north of London. It is a bucolic spot that reflects her love of nature and water. “She’s in a happy and secure place,” Charles, 9

Earl Spencer tells PEOPLE in this week’s cover story.

It is also somewhere that her sons, Prince William and Prince Harry, can visit peacefully.

“I never go to Diana with them. It’s very much their time there,” says Spencer. “But I think I think it’s very important for them to be there with her. It is, luckily, very tranquil here and they can come and go as they wish whenever they want. And that’s very lovely for me to know that.”

Spencer is joined by Diana’s friend Sir Richard Branson, her wedding dress designer Elizabeth Emanuel, charity partner Vivienne Parry and many others in remembering the late princess in PEOPLE’s cover story and on a two-night television event from PEOPLE and ABC,

Last month, on what would have been Diana’s 56

birthday, William and Kate, their children Prince George and Princess Charlotte, Prince Harry and members of the Spencer family attended a poignant re-dedication ceremony at the recently renovated island, where rhododendrons and her favorite forget-me-nots have been re-planted.

Diana is also symbolically evident in the engagement ring worn by the daughter-in-law she never knew, Princess Kate.

“It’s lovely,” says Spencer. “I love the fact that there’s still such veneration inside her immediate family for what she was and what she meant . . . It shows what a good mother she was.”

For full PEOPLE coverage of the 20th anniversary of Princess Diana’s death:

a two-part television event from PEOPLE and ABC, airs on ABC Aug. 9 and 10 at 9 p.m. E.T.

is streaming on the new People/Entertainment Weekly Network (PEN). Go to PEOPLE.com/PEN, or download the PEN app on your favorite mobile or connected TV device

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