Watch: New details announced for Prince Philip's funeral
The guest list for the slimmed funeral of Prince Philip has been confirmed, with the members of his immediate family making up most of the numbers.
With four children, eight grandchildren and a growing number of great-grandchildren, it was expected that the funeral would mostly be made up of his own direct relatives.
Three of his family members from the German side of his family have also been confirmed.
But there is one person on the list who is not directly related to the Duke of Edinburgh, a close friend who will unite with the family to pay her respects.
Countess Mountbatten of Burma had been a friend of the duke for several years, and they shared a passion for the equestrian sport of carriage driving.
Known as Penny to her friends, Penelope Knatchbull was a frequent visitor to Philip after he retired in 2017 to Wood Farm on the Sandringham estate.
At 68, she was a few decades younger than her close friend, but Philip still managed to impart to her a love for his favourite sport.
Who is Penny Knatchbull?
Penelope Meredith Mary Knatchbull was born on 16 April 1953, in London. Her mother Marian Hood is still alive, but her father Reginald Eastwood died in 1980.
He was a businessman who had success backing the Angus Steakhouse restaurant chain.
The countess had one younger brother who died in 2013. She was educated in Switzerland and went to the London School of Economics.
She married Norton Knatchbull in 1979, who was the son and heir of the 2nd Countess Mountbatten and Lord Brabourne.
Knatchbull's cousin is Prince Charles, and Prince Philip was his uncle. Charles was the best man at the couple's wedding.
The wedding was just two months after the death of Lord Mountbatten, who was Prince Philip's uncle and Knatchbull's grandfather.
Lord Mountbatten was murdered by the IRA and his death had a profound impact on the whole Royal Family.
The Knatchbull family seat, or family home, is Broadlands in Hampshire - which is where the Queen and the Duke of Edinburgh spent their honeymoon in 1947.
Prince Charles and Diana also spent three days there for their honeymoon in 1981.
Until 2005, the countess was known as Lady Romsey, and her husband was the Baron Romsey.
Then she became the Lady Brabourne, when her husband's father died.
In 2017, she became the 3rd Countess Mountbatten of Burma, after the death of her husband's mother.
When did she and Prince Philip become friends?
Philip and the countess long ran in the same circles, and so they had likely known each other for some time.
But they are reported to have become close when the duke offered support during a sad time for the countess.
Her third child, Leonora, died in 1991 of kidney cancer, aged just five.
It's reported that soon after this Philip began to invite her on carriage rides, and by 1994, he began to teach her how to do it herself.
They were often seen around the Royal Windsor Horse show together, a favourite event of the Queen.
Many pictures show her with the Queen too.
The countess was also seen with Philip riding mini motorcycles around the carriage driving course at Windsor.
Her nickname with palace staff was said to be 'and also' because she was automatically added to any guest lists for Philip's events.
What is carriage driving?
The shared love of carriage driving is said to be what united the countess and the duke.
It's been reported that the enthusiasm the duke's younger friend showed for it is what kept him competing well into his 90s.
The sport is also loved by his youngest granddaughter Lady Louise Windsor.
According to Horse Sport Ireland, it's a discipline without riders, and involves a driver sitting on a vehicle drawn by a single horse, a pair or a team of four.
There are three tests for the driver and horses - dressage, marathon and obstacle driving.
The site explains: "Dressage is a sequence of compulsory movements in an enclosed arena. Judges award the smoothness of the movements, the obedience of the horses, impulsion and correct positioning.
"Marathon is a course of natural obstacles over a maximum of 22 km, including natural and artificial obstacles.
"Obstacle driving is a cone course that tests the horse shape after the marathon. The aim is to drive through a narrow track outlined by cones with balls balanced on top."
Philip was credited with bringing carriage driving to the UK, starting it himself when he had to give up polo.
Rowena Moyse from Gowerton, Swansea, told the BBC: "It was very much the love of his life."
In 2020 she said: "One of the last memories I have of him is sitting in his car [at an event], leaning out of the window with his head on his arm fast asleep amongst the crowd of carriage drivers.
"There was no security around him. It was just nice to see him able to be in that situation... the fact that he could relax amongst friends."
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