The fictional aristocrats of “Downton Abbey” have real-life royalty among their fans. Queen Elizabeth II is reportedly a big fan of the British period drama.

Brian Hoey, author of “At Home With the Queen,” revealed that the monarch enjoys finding historical inaccuracies in the show. “She loves to pick out the mistakes,” Hoey told People. “They do tend to get it right. However, 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.”

Downton Abbey Even the queen wants to follow Mary's (Michelle Dockery) search for love on "Downton Abbey." Photo: Nick Briggs/Carnival Film & Television Limited for "Masterpiece"

Downton Abbey” prides itself on historical accuracy. The producers have a historical adviser, Alastair Bruce, who helps the show stay true to life in the 1920s. But Bruce has acknowledged that he can’t make the show perfect. In Season 4, Mary (Michelle Dockery) was mourning the death of her husband Matthew (Dan Stevens), but the show didn’t keep her in dark clothing quite as long as she should’ve been. “I think the producers’ desire was not to have Michelle Dockery stuck in black for the whole of the series,” Bruce explained to Deadline in 2014. “We are delivering entertainment, not a documentary.”

Even with minor historical inaccuracies, the royals still love the show. The queen's grandson, Prince William, also admitted that he and his wife, Kate Middleton, enjoy watching it together. “[Prince William] said that he was really looking forward to the episode that we run on Christmas day [in the U.K.], which is the season finale [for American viewers] … so we know that William and Kate are fans,” executive producer Gareth Neame told Vanity Fair in December.

Catherine, Duchess of Cambridge, even visited the “Downton Abbey” set while they were filming Season 6. She took pictures with the whole cast and met with each department to see how the show was made.

There has been no comment on how the royal family is handling the news that Season 6, which returns to PBS on Jan. 3, will be the final season.