It has been more than four years in the making but the Duke of Cambridge and the Duke of Sussex will today unveil a statue of their mother, Diana, Princess of Wales, in a brief but poignant ceremony reuniting them on what would have been her 60th birthday.

The brothers will stand shoulder to shoulder in the Sunken Garden at Kensington Palace, the late Princess’s former home, where they are each expected to speak fondly of her legacy.

They will be joined at the private ceremony by a small coterie of Diana’s closest family and friends, including her brother Earl Spencer and sisters Lady Sarah McCorquodale and Lady Jane Fellowes.

The six-strong “statue committee” headed by Jamie Lowther-Pinkerton, the brothers’ former private secretary, will also attend, alongside sculptor Ian Rank-Broadley and garden designer Pip Morrison.

Commissioned in January 2017 by Prince William and Prince Harry, who had long wanted a permanent memorial to their mother, the statue (by Ian Rank-Broadley whom you can read about below) will recognise her “positive impact.”

Princess Diana sculptor

The brothers have been intimately involved in every aspect of its design, liaising with the committee throughout to ensure the “beautiful” and “informal” memorial reflects the late Princess’s youthful and playful nature.

“It is not in any way austere or imperious,” said a source close to the project. “Both brothers wanted to ensure that the artwork is something that really resonates with the public.

“It’s absolutely charming and such a fitting tribute.”

Throughout the 30-minute ceremony, all eyes will be on the body language between the warring brothers, both of whom are determined to put their differences aside and to remain “professional.”

Will the statue reunite the broken brothers? 

The pair have barely spoken since the Sussexes moved to California, the rift only deepening in recent months as Prince Harry made a raft of accusations about his family in various interviews. See Camilla Tominey‘s video analysis here.

Before the Duke and Duchess stepped back from their public roles, the brothers are said to have spent “weeks” deciding where exactly the statue should be located in the grounds of the royal residence in west London, which will always be synonymous with the Princess. 

The committee has spent the last few years liaising with all involved and sourcing funds from private investors said to include Sir Elton John and David Furnish.

The group includes Julia Samuel, a godparent of Prince George and a close friend of the Princess, Lady Sarah, Gerry Farrell, the co-owner of London’s Sladmore gallery, Guy Monson, a financier and trustee of the Invictus Games, and John Barnes, chief executive of Historic Royal Palaces.

Gardeners have spent almost two years redesigning the Sunken Garden to incorporate forget-me-nots, ballerina roses, dahlias and sweet peas to reflect the Princess’s tastes and personality.

Graham Dillamore, deputy head of gardens and estates at Historic Royal Palaces, worked in the garden while the Princess was alive and led the team that carried out the replanting.

He said: "While she was in residence at Kensington Palace, Diana, Princess of Wales, regularly admired the changing floral displays in the Sunken Garden and would always stop to talk with me and the other gardeners who cared for it.

"Over three decades later, I’m honoured to have been part of the team preparing the garden for the installation of this statue.

"We’ve incorporated a number of the Princess’s favourite flowers into the design, and I hope that visitors to the palace and gardens will enjoy its peaceful setting, and take a moment to reflect on the life and legacy of the Princess."

Royal fans have been gathering outside Kensington Palace to pay their own tributes ahead of the unveiling.

Credit: Leon Neal/Getty

The gardeners have spent 1,000 man hours working on the planting, which includes more than 200 roses, 500 lavender plants, 300 tulips, 100 dahlias and 100 forget-me-nots.

In total, 50 different varieties have been planted, including wisteria, agapanthus, clematis, hydrangeas, hostas, violas and petunias.

When can I visit the statue? 

From tomorrow, the public will have unrestricted access to the statue in the Sunken Garden, which is open throughout the day.

But all concerned are determined that it will not become a place of pilgrimage, lost in a sea of flowers.

“Any flowers or tributes left there will be removed and placed at the golden gates, where they have always been permitted,” a source said.

“There is a strong desire that this does not become a shrine.”

A team of conservators working for Historic Royal Palaces will be tasked with the maintenance of the statue, adding it to their roster of responsibilities at Kensington Place that includes interiors, collections and the existing Queen Victoria and King William III statues.

The security team that patrols the site 24/7 will be on hand to ensure it is not damaged, while additional staff monitor the gardens during opening hours.