Charles Spencer hates it when people tell him where they were when his sister Princess Diana died

Princess Diana's 61-year-old brother, the 9th Earl Spencer, said on the latest episode of broadcaster Gyles Brandreth's Rosebud podcast: "I try and be really busy on the 31st of August because it's just terribly sad, really.

"I tell you what I do find quite difficult, and this probably sounds ungracious, but occasionally, total strangers come up and feel they must tell me where they were when they heard that she died, sort of thing.

"And I'm sure that's helpful to them. It's not entirely helpful to everyone else."

Charles then recalled a woman from South Dakota, USA, who claimed to him that she grew up with the late Princess of Wales - who was married to now King Charles, 76, from 1981 until 1996 - in the north-central state.

He said: "And I had, actually, this year, I had - I mean, it's comic really - I had a lady from South Dakota, who clutched me to her ample bosom, and said that I may have thought I grew up with Diana, but actually she did in South Dakota.

"So you just have to smile. It doesn't matter."

Former UK Conservative Party Member of Parliament (MP) Gyles, 77, revealed his neighbour still has a shrine to her in his home, which the "successful businessman" created following Princess Diana's death in 1997.

He shared: "It's a curious thing. I have a neighbour in my part of South London who's got a shrine to her in his home, which he has kept since 1997 with candles and flowers and photographs of her.

"This is a successful businessman."

Charles reacted: "It's extraordinary, isn't it?"

The 9th Earl Spencer - who has sisters Lady Sarah McCorquodale, 70, and 68 year old Jane Fellowes, Baroness Fellowes - puts Princess Diana's popularity down to how relatable she was to millions of people across the world.

Charles said: "I think it's different things to different people.

"And I think particularly to women of a similar age, they really invested their lives in hers.

"So they ran, maybe they had an unhappy marriage. Maybe they battled an eating disorder [Princess Diana battled bulimia]. There was plenty of Diana to look into and take your bit out of, almost like a horoscope, you know. You can make it make sense for you."

He added: "Julian Fellowes, if I may quote him a second time, he's a close friend of mine. And he said, 'I think part of her appeal, of course, you know, she married into the royal family, she was beautiful and, you know, very charismatic.'

"But he also said, like the great film stars, there was something unhappy in there that really triggered an emotional response."