Harry and Meghan Markle have relocated from California, six years after the Megxit crisis, with Prince Archie and Princess Lilibet.

Just weeks ago during a brief summer stay, Harry took both his children, who are now enrolled in British schools, to see Diana’s resting place for the first time.

Diana is buried on a tiny island in the Round Oval Lake on the Althorp estate in Northamptonshire – the Spencers ancestral home where Diana’s brother Earl Spencer is now the custodian.

Next year marks the 30th anniversary of the princess’s sudden death in a Paris car crash.

Harry revealed in the summer how he makes lemon drizzle cake to mark the day each year as a “sweet” way to remember his mother.

Diana – the ex-wife of Britain’s King Charles – was tragically killed on August 31st, 1997 when her sons Harry and William were just 12 and 15.

The anniversary comes just three weeks before Charles Spencer prepares to release his deeply personal memoir to counter “untruths” about her life.

His new book Swan Song: Diana, My Sister is due out on September 22nd and is set to contain “many revelations that will draw considerable attention”, according to its publisher.

He famously delivered a passionate eulogy at her funeral, pledging the princess’ “blood family” would protect William and Harry “so that their souls are not simply immersed by duty and tradition, but can sing openly as you planned”.

He said of writing the memoir: “With the 30th anniversary of Diana’s tragic death on the skyline, I’ve been inundated yet again with requests for interviews about my sister.

“This has convinced me to write down my own thoughts and memories, once and for all, rather than having the discomfort of again reading the opinions of others, many of which are based on untruths that have become accepted over time.”

Daniel Bunyard, publishing director at Penguin Random House UK, said: “While these pages contain many revelations that will draw considerable attention, readers will find, for the first time, but also for all time, a fitting tribute to the beloved woman who was Princess Diana.”

Devoted fans of the princess usually gather each year at the gates of her former London home Kensington Palace to leave flowers and other tributes.

In the Palace’s Sunken Garden stands the bronze statue of Diana commissioned by the now-Prince of Wales and Harry, and unveiled by the estranged brothers together in 2021.

The pair put on a united front despite their rift to reveal the sculpture on what would have been their mother’s 60th birthday.

Their fallout stretches back to before Harry’s 2018 wedding to American-born former Suits actress Meghan.

Harry was apparently angered at what he perceived to be his brother’s “snobbish” attitude towards his bride, after William questioned whether he should rush into things.

But their relationship deteriorated further during Megxit and after Harry’s accusations against William and other family members in his Oprah interview, Netflix documentary and memoir Spare.

William and the Princess of Wales have yet to comment on Harry and Meghan’s return.

In 2007, William and Harry commemorated 10 years since their mother’s death together, staging a pop concert at Wembley on what would have been her 46th birthday, and an emotional memorial service in London on the actual anniversary.

The day before the 20th anniversary in 2017, the siblings were side by side as they viewed tributes left for the princess outside Kensington Palace.

The brothers will be expected to mark this year’s anniversary separately, with a reunion on the 30th anniversary looking, at this stage, unlikely.