LONDON, United Kingdom (AFP) — Princes William and Harry prepared to pay tribute to their late mother Princess Diana on Wednesday for the 20th anniversary of her death as well-wishers left candles and flowers outside the gates of her former London residence.

Handwritten notes on bouquets left in front of Kensington Palace read: “Diana, a brave princess, your sons have your courage” and “Dear Diana, our country was so very lucky to have you”.

“I came 20 years ago with my mother, and my son, who is now 21,” said teaching assistant Stephanie Davinson, 52, after leaving a bouquet.

“I’m doing it for her sons, they’re following in her footsteps, I think there’s a lot of her in them”.

Pictures were left of Diana, her children and grandchildren, while hardcore fans of the princess brought a cake bearing her picture.

“It doesn’t matter now or in say 100 years, it will still be the same kinds of feelings towards her, in a really good way,” said Australian tourist Clint Wilde.

William and Harry will tour Diana’s memorial garden at the palace later on Wednesday together with representatives from the charities she supported, including those helping AIDS sufferers and children in need.

“The engagement will allow the Princes to pay tribute to the life and work of their mother the day before the 20th anniversary of her death,” said a spokeswoman for Kensington Palace where the princes now live.

“Together, they will reflect on the significant achievements of the Princess, and the legacy of her work which continues to resonate with so many today,” she said.

Diana’s untimely death two decades ago on Thursday shocked the world.

“She was this ray of light in a fairly grey world,” 35-year-old William, her eldest son and second in line to the throne, said in a new documentary for the anniversary.

The life of Diana — a shy, teenage aristocrat who suddenly became the world’s most famous woman — and her tragic death at 36 still captivates millions across the globe.

Two decades on, her sons William and Prince Harry only now feel able to talk publicly about her death, a seismic event which continues to resonate in the monarchy and British society.

– No more stiff upper lip –

Diana died in a car crash in Paris in the early hours of August 31, 1997, along with Dodi Fayed, her wealthy Egyptian film producer boyfriend of two months, and a drink-impaired, speeding driver Henri Paul, who was trying to evade paparazzi.

No public events are planned for Thursday.

The tributes outside Kensington Palace were nothing like the sea of flowers laid in the week between her death and her funeral: an outpouring of national grief that commentators are still grappling with.

William and Harry have spoken of struggling to comprehend the “alien” wave of public mourning among people who didn’t know their mother, at a time when they, aged 15 and 12, could not process their loss.

Britain, the nation of the stiff upper lip, was now wailing and hurling flowers at a hearse.

– Fragility and steel –

Diana married Prince Charles, the heir to the throne, in 1981, but their marriage collapsed under the strains of public duty and their incompatibility.

The monarchy’s shining star, now a fashion icon, humanitarian and self-styled “queen of hearts”, found herself cast out of the royal family in the 1996 divorce she did not want but had made inevitable with an unprecedented and explosive television interview.

With all her mistakes and frailties played out in public, Britons felt wrapped up in Diana’s life and the complexity in her character still fascinates.

A testament to her enduring impact, British newspapers have been filled this month with special pull-outs and magazine articles covering all facets of Diana’s life.

William has said he tells his children, Prince George, four, and Princess Charlotte, two, about the Granny Diana they will never meet.

“When you have something so traumatic as the death of your mother when you’re 15, it will either make or break you,” William said in the “Diana, 7 Days” BBC documentary.

“And I wouldn’t let it break me.”