'Downton Abbey' Episodes: What Historical Mistake Did Queen Elizabeth Spot in British Drama?

The British historical drama "Downton Abbey" has a lot of celebrity fans, and even some royal fans, since it was just learned that 89-year-old Queen Elizabeth II, who is set to become the longest-reigning English monarch loves to spend her leisure time watching the show and finding out what happens to the Crawley family next.

But that's not all Queen Elizabeth loves to do. During an interview with PEOPLE, Brian Hoey, who wrote the book "At Home with the Queen" said that the monarch actually loves to check the historical consistencies of the show, since she knows Highclere Castle (the place where they film the series) inside and out.

"She loves to pick out the mistakes," said Hoey, adding that because of the show's historical advisor, "they do tend to get it right."

However, there is one time that the show did commit a mistake. For regular viewers, the mistake might have passed unnoticed, but not to the eagle-eyed Queen.

"The Queen did notice on one episode that there was a young so-called British officer wearing medals which had not been awarded when he was supposed to be alive. He was fighting in the First World War and the medals on his chest did not come in until the Second World War," he said.

Aside from her love of "Downton Abbey," there are actually a lot of other interesting things about Queen Elizabeth. Her cousin Margaret Rhodes shares, "She is quite deadpan and yet has a wonderful rollicking sense of humor."

The Queen is apparently great at mimicking things, including an aircraft sound. "When Concorde used to fly over Windsor Castle, she developed an ability to mimic Concorde," said Sally Bedell Smith, author of "Elizabeth the Queen: The Life of a Modern Monarch."

Many people might expect that she has extremely high musical tastes, but it would surprise you to learn that the Queen does not like opera or the ballet that much. She much prefers musical theater, "but it has to be the older musical theater by Rodgers and Hammerstein, like 'Carousel,' 'Oklahoma,' or 'South Pacific.' And she's a huge fan of the big band sound," said Smith.

At the same time, the monarch has a deep fascination about space and space travel. Ingrid Serward, who wrote the book "The Queen's Speech" revealed that Queen Elizabeth is "really knowledgeable about the stars and astronomy," and she loves meeting astronauts too.