Queen Elizabeth has been married to her husband Prince Philip for nearly 73 years, and though they are said to be very much in love, it does not mean that they’ve had their occasional fights over the years.

Royal expert Ingrid Seward published a book last month called “Prince Philip Revealed,” and she has since spoken out t say that one of her favorite moments that she uncovered in her research came at a time when the Queen was royally livid at Philip.

The royal couple was touring Australia back in 1954, when they were given a rare weekend off. Cameras were still rolling at the time, however, as the couple was filming a documentary about their visit. Seward said that things quickly went downhill as tempers soon flared.

“Their tempers were very frayed,” she told Fox News. “This film crew was standing outside their little holiday villa. The next thing they knew, Prince Philip appeared on the balcony, followed by a tennis racket and a pair of tennis shoes thrown at his head. The queen came out and shouted at him to come back. She then grabbed [Philip] and dragged him back inside. Of course, you can imagine how this sort of frumpy press secretary at the time was absolutely terrified.”

According to Seward, the royal press secretary told the members of the crew that they would be arrested if they didn’t shut off the cameras.

“He ran over to the crew and said, ‘We cannot have this on film,’” said the longtime royal biographer. “‘This is a disaster. Give me your film. You weren’t mean to be filming this.'”

After some back and forth, the film was given to the Queen, who came out afterwards to graciously thank the crew in person.

“I am sorry for that little interlude,” she reportedly said to them. “But as you know it happens in every marriage, doesn’t it?”

Seward added that the Queen and Philip have had their fair share of fights over the 73 years they’ve been together.

“He was quite sharp with his wife,” she said. “He used to drive at top speed everywhere, which would make her very nervous. So she would start to take deep breaths. He would then tell her, ‘If you carry on breathing like that, I’ll put you out of the car.’ There was a time when a person sitting next to her said, ‘Why don’t you tell him off?’ She said, ‘Because I know he will stop the car and put me out!’”

“But the queen gives it back just as much,” Seward added. “He would call her a bloody fool and accuse her of talking rubbish. She’ll then speak in riddles as he tries to figure out what she’s talking about.”

Despite these minor issues, the Queen and Philip’s marriage has managed to stand the test of time. Seward believes that Philip’s dedication to duty could be the secret behind their long-lasting union.

“I think it’s very hard to know what a marriage secret is between two people,” she said. “But I think for them, he decided that his job and his duty are to support her – it’s an all-encompassing job. Philip decided he must support the institution of the monarchy, which mean looking after the queen at all times. He is aware that the people only want the royals if they can respect them. So that became very important to him.”