Prince Philip has a very specific demand when it comes to dinner conversations with guests: he decides the flow of the conversation. Brian Hoey, a distinguished journalist and broadcaster who focuses mainly on the royal family, discusses this further in his book “Not In Front Of The Corgis: Secrets Of Life Behind The Royal Curtains,” which was released in 2011.

“When Prince Philip gives a private dinner, he likes to decide the subject for conversation,” the journalist wrote.

Apart from steering the conversation toward his preferred topic, the Duke of Edinburgh is quite particular on a person’s amount of knowledge on the subject. A guest, to her dismay, learned about this peculiarity after she could not contribute to the duke’s highlight of the night: deciduous trees. However, one cannot be too knowledgeable as upstaging Prince Philip can just as well “ruin the occasion.”

“If guests are not quite as knowledgeable as they should be, the Prince can become very touchy — but if someone is more expert than him, it can just as easily ruin the occasion,” wrote Hoey.

There is a way to avoid making the 97-year-old “less than pleasant,” the author continues. One may phone the prince’s office in advance to learn about his current interests and do some research prior to the meeting — enough to contribute intelligently but not enough to upstage him.

Guests must also be aware to not disrupt the prince when he’s watching the television. Unexpected guests will be given a drink and asked to wait for him while he’s taking care of “urgent business.”

“He will order his doorman to give the man a drink and tell him His Royal Highness won’t be long as he is involved in urgent business,” notes Hoey in his book.

In addition to these quirks, guests must also be wary of overextending their stay, lest they may be sent packing by the host. “Members of the Royal Family, without exception, hate it when guests overstay their welcome,” Hoey also adds.

When faced with overstaying guests, the host member of the royal family will motion for their butler, asking whether the guest’s car has arrived. This is the cue for the butler to have the guests’ vehicles be in waiting at the driveway, prompting the host to bid them farewell.

These quirks are just some of the peculiarities that Prince Philip has been observed to follow. Guests are called to take notice of these in order to assure that the Prince and his guests become more comfortable during these small encounters.

Prince Philip Prince Philip, Duke of Edinburgh, attends the wedding of Princess Eugenie of York to Jack Brooksbank at St. George's Chapel on October 12, 2018, in Windsor, England. Getty Images/Alastair Grant-WPA Pool