Queen Elizabeth is full of royal nicknames — to Prince George, she's known simply as "Gan Gan"

Queen Elizabeth and Sophie, Countess of Wessex share a close bond — and it’s reflected in what Sophie calls the monarch, who just happens to be her mother-in-law!

The royal women joined forces for a Buckingham Palace reception celebrating the work of the Queen Elizabeth Diamond Jubilee Trust to prevent unnecessary blindness on Tuesday, and Sophie — who is married to the Queen’s youngest son, Prince Edward — even took center stage by giving a speech. Not only did Sophie highlight the Queen’s lifelong work to better the Commonwealth, but she also revealed what she calls the monarch in less formal settings.

After referring to the Queen as “Your Majesty” several times in her speech, Sophie got more personal and called her “Mama.”

“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,” Sophie said.

Queen Elizabeth II and Sophie, Countess of Wessex
Credit: Max Mumby/Indigo/Getty
Sophie Countess of Wessex Queen Elizabeth
Sophie, Countess of Wessex, and Queen Elizabeth
| Credit: Kirsty O'Connor - PA Images/Getty

While she’s Queen Elizabeth to millions around the world, the royal family has special nicknames for each other. In a 2016 documentary honoring Queen Elizabeth‘s milestone 90th birthday, Kate Middleton opened up about her children’s special relationship with the monarch – and shared their nickname for her.

Kate told ITV’s The Queen at Ninety, “George is only 2 ½, and he calls her ‘Gan-Gan,’ ” Kate said. “She always leaves a little gift or something in their room when we go and stay, and that just shows her love for her family.”

The Christening Of Princess Charlotte Of Cambridge
Prince George and Queen Elizabeth
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And Queen Elizabeth isn’t the only one with a royal nickname. Prince George calls father Prince William simply “Pops,” while Princess Charlotte is known as both “Lottie” and “Mignonette.” Even Kate is a nickname, as the Duchess of Cambridge’s full name is Catherine.

Prince Harry, Duke of Sussex, Meghan, Duchess of Sussex and their baby son Archie Mountbatten-Windsor
Archie, Meghan Markle and Prince Harry
| Credit: Samir Hussein/WireImage

Meghan Markle also recently shared her monikers for the two main men in her life: Prince Harry and son Archie, born May 6. She calls Prince Harry by the short and sweet nickname “H” in the ITV documentary Harry & Meghan: An African Journey.

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In a video from their visit with Archbishop Desmond Tutu in South Africa, Meghan is also heard calling Archie “Bubba.”

“Say hello! Hello, hi,” says Markle, before she realizes that he’s drooling. “Oh, Bubba!” Luckily, dad Prince Harry was on hand to deal with the dribble.