Last Friday, the palace shared the incredibly sad news that Prince Philip had died at the age of 99.
Due to ongoing COVID restrictions, only 30 people will be attendance at the funeral service, including Prince Charles, Prince Andrew, Princess Anne and Prince Edward.
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Also in attendance will be the Countess Mountbatten of Burma, Penelope Knatchbull, who had always been one of the closest companions of both the Queen and the Duke of Edinburgh.
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Known informally as Penny, the Countess is the only daughter of butcher-turned-businessman Reginald Eastwood and she became close to the royal family through her relationship with Norton Knatchbull, 3rd Earl of Mountbatten.
Penelope was an immediate hit with the royals, but particularly impressed the Queen and Philip when she was first introduced by Norton in 1975.
A royal insider remembered her as "one of the most natural young women I have ever met, outgoing but not brash or flirty".
The Countess has been pictured with the royals at many events
Norton's close friendship with the major royals served as the perfect springboard for Penelope to get closer to the family.
The Earl had attended prestigious independent school Gordonstoun with Prince Charles as a child, with the Prince of Wales serving as best man at the couple's wedding ceremony in 1979.
Between 1981 and 1986, Penelope gave birth to three children, Nicholas, Alexandra and Leonora. However, tragedy struck in 1991, when Leonora contracted liver cancer and died at the age of five.
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The Countess and Prince Philip were close friends
Following this shocking tragedy, Countess Mountbatten grew closer to Prince Philip and the Queen.
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Despite an age difference of more than 30 years, a shared love of the outdoors allowed their friendship to flourish, which only strengthened after Philip taught the Countess to drive carriages in 1994.
Prince Philip and Penelope were both big fans of carriage driving
While Penelope was seen in public riding alongside Phillip, her friendship with the Queen grew behind closed doors.
However, it was the strength demonstrated following her husband's affair in 2010 that particularly impressed Her Majesty and allowed their companionship to become a more public affair.
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Refusing to let Norton's departure interrupt royal duty, the Countess took over the running of the Broadlands estate. Despite the family connection between Norton and the royals, a friend close to the family said that "the Queen and Phillip [couldn't] forgive him for what he did to Penny".
Norton Knatchbull and Penelope Eastwood on their wedding day
From that point onwards, the Countess has been a fixture at many royal events of consequence; amongst palace staff, she is nicknamed 'and also' as no guest list is considered complete without her.
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