Here's a cute nickname little Prince George has for Queen Elizabeth

As Queen of England, Elizabeth II has many titles, but there is a very special one that is only reserved for her great-grandchildren. A documentary celebrating her 90th birthday revealed how Prince George calls her.

The historic ITV documentary features Duchess Kate’s first solo TV interview, and it includes more contributions from members of the Royal Family than any other film about the British royals, as Telegraph reported.

Our Queen At Ninety was first broadcasted on Easter Sunday 2016, and gained privileged access to the Royal Family light-hearted side while it paints an intimate portrait of the Queen, who recently turned 92-years-old.

Among the array of royal contributors to the TV movie, the 36-year-old Duchess of Cambridge revealed the special nickname Prince George uses when referring to his great-grandmother.

It would be hard to imagine a toddler calling his dear great-grandmother ‘Your Majesty,’ and Prince George came up with a unique and affectionate way to call her.

Middleton joined the Prince of Wales, Duchess of Cornwall, her husband the Duke of Cambridge, Prince Harry, the Duke of York, Princesses Beatrice and Eugenie, the Countess of Wessex, and Peter Phillips, as Hello! reported.

In the candid conversation, Middleton addressed the subject of the Queen’s relationship with her great-grandchildren, and she revealed the intimate name Prince George gave her: Gan-Gan.

The Duchess shared that any time the family went to visit the Queen, she made sure to leave a little gift for the little ones in Middleton’s children’s rooms.

Our Queen At Ninety was released a month before the Queen’s 90th birthday. During that year’s Trooping of the Colours, the annual official celebration of her birthday, then 1-year-old Princess Charlotte made her first public appearance.

But way before that, the media was so curious about anything related to the Princess, by then the youngest member of the Royal Family, and the documentary made sure to touch the matter when interviewing Middleton.

The Duchess of Cambridge shared that Queen Elizabeth II was truly excited about welcoming a girl as great-granddaughter. Middleton said that she knew the Queen was going to be one of the first visitors when they got back to Kensington Palace.

It took the filmmakers, under the direction of Ashley Gething, almost two years to put together the 1 hour 28 minutes special. It showed the Queen as both family woman and head of state and a family woman.

Middleton talked about the special bond she had built with her mother in law and she said how much she appreciated her guidance and support when she had to learn how to live under the public view and its heavy scrutiny.

‘She's been very generous in not being forceful at all and in any of her views, but I feel she's been there, a gentle guidance really for me,’ she shared.

Prince William, Duke of Cambridge, also paid his tributes to his grandmother, and he praised her for providing him with a strong structure while at the same time giving him the opportunity to shape his own life.

‘Growing up, having this figurehead, having this stability above me has been incredible. I have been able to explore, understand, slightly carve my own path. I greatly appreciate and value that protection,’ he said.

Apart from the royals, the documentary features interview with celebrities and politicians such as David Beckham, Justin Trudeau, and Barack Obama. Read more on our Twitter account @amomama_usa