The Queen was incredibly close to the Queen Mother, and she was no doubt in her thoughts on Tuesday, which marked the 19th anniversary of the royal's death.
The Queen Mother passed away on 30 March 2002, aged 101, and the monarch addressed the nation with a moving public speech one week later.
On the eve of her mother's funeral, the Queen, dressed respectfully in a black outfit, delivered a televised address from Windsor Castle, during which she thanked the public for their support.
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WATCH: The Queen's moving speech following the Queen Mother's death in 2002
She said: "Ever since my beloved mother died over a week ago I have been deeply moved by the outpouring of affection which has accompanied her death.
"My family and I always knew what she meant for the people of this country and the special place she occupied in the hearts of so many here, in the Commonwealth and in other parts of the world.
"But the extent of the tribute that huge numbers of you have paid my mother in the last few days has been overwhelming. I have drawn great comfort from so many individual acts of kindness and respect."
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The Queen and Prince Philip after the Queen Mother's state funeral in 2002
The Queen also paid tribute to the Queen Mother saying: "Over the years I have met many people who have had to cope with family loss, sometimes in the most tragic of circumstances.
"So I count myself fortunate that my mother was blessed with a long and happy life. She had an infectious zest for living, and this remained with her until the very end. I know too that her faith was always a great strength to her."
Born Elizabeth Bowes-Lyon on 4 August 1900, she was the wife of King George VI. Her husband had unexpectedly become King in 1936 following Edward VIII's abdication.
As a result, the couple's eldest daughter, Princess Elizabeth, then became the heir to the throne.
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The Queen Mother celebrating her 101st birthday in 2001
King George VI died on 6 February 1952 in Sandringham, and Elizabeth became Queen at the age of 25. Her mother became known thereafter as the Queen Mother.
She was a popular member of the royal family and continued an active public life up until a few months before her death.
Buckingham Palace released a statement on 30 March 2002, which read: "The Queen, with the greatest sadness, has asked for the following announcement to be made immediately: her beloved mother, Queen Elizabeth, died peacefully in her sleep this afternoon at Royal Lodge, Windsor. Members of the royal family have been informed."
The Queen and the royals had also mourned the loss of the monarch's younger sister, Princess Margaret, who passed away just seven weeks before the Queen Mother.
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