sophie wessex and the queen

The Countess of Wessex's affectionate nickname for the Queen revealed

The royals were attending a glittering reception at Buckingham Palace on Tuesday night

Ainhoa Barcelona

The Countess of Wessex and her mother-in-law the Queen are known to have a very strong bond, but on Tuesday night, royal watchers were given a glimpse into their close relationship as Sophie addressed Her Majesty during a speech. The royals were attending a glittering reception at Buckingham Palace to celebrate the success of the Diamond Jubilee Trust, with Sophie paying tribute to the charity's work, as well as the monarch.

The Countess, who has been campaigning to improve eye health worldwide since 2000, spoke in front of 200 guests and addressed the Queen, saying: "I feel in a way that I have been your eyes, having travelled to Malawi, Bangladesh and India to see the work of the Trust first-hand, witnessing the ambitious initiatives being carried out in Your Majesty's name, and ensuring that the intended legacy would be real and long lasting. I am very happy to say that Your Majesty's honour has been more than upheld."

Sophie gave a speech, addressing her mother-in-law the Queen

Sophie, who looked elegant in white, then referred to the Queen as "Mama" as she continued: "Mama, when I have returned from my travels I have been so proud to share with you the work I have witnessed being carried out under the umbrella of the Queen Elizabeth Diamond Jubilee Trust and the care of so many people working so hard to save and cure sight.

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"Each time you have listened with interest and been eager to hear of how the work is going, and each time I have been stunned as you have shared with me your deep knowledge of each of these countries, not top level observations, but personal experience, demonstrating to me time and again the real affection you have for all people of the Commonwealth and why that affection is so abundantly returned by them to you."

The Queen greeted around 200 guests at the reception

At the reception, the Queen personally greeted around 200 health professionals and supporters from across the Commonwealth who have helped saved the sight of 22 million people in five years, through a project led by The Queen's Diamond Jubilee Trust.

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Sophie's speech wasn't the first time the royal family have openly revealed their affectionate nicknames for the monarch. At her 92nd birthday party at the Royal Albert Hall, Prince Charles referred to his mother as "Your Majesty" before switching to the rather familiar "Mummy" when addressing his mother on stage, prompting the Queen to roll her eyes and laugh.

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