In the past, members of the royal family like Prince Harry and Prince William have shared stories about Queen Elizabeth’s light-hearted sense of humor. However, the royal’s personal assistant, Angela Kelly, claimed she managed to shock the monarch with a wicked prank.

Kelly revealed Elizabeth was left “horrified” by the stunt and jokingly fired her. In her new book, “The Other Side of the Coin,” the senior dresser recalled her plan to trick the monarch during her Royal Tour to Australia in 2006.

The Sun reported that the designer claimed Queen Elizabeth was excited to see a kookaburra bird and was disappointed she hadn’t seen one. However, during Kelly’s trip to the market, she spotted a toy version of the bird for her boss but realized she had the opportunity to give it to the monarch in a unique way.

“I had something in mind I thought the Queen would enjoy,” she wrote.

When Kelly returned to their temporary residence in Australia, she placed the toy bird in a cage on the balcony. Once Queen Elizabeth arrived, the designer set her plan into motion.

Kelly told the monarch that she saw a “funny-looking grey bird” through the window. “The Queen looked outside and shouted, ‘It’s a kookaburra!’ I went to open the cage doors, and she said loudly, ‘No! Don’t do that! It will fly away!’ and was behind me in a flash,” she wrote.

“Turning to her Majesty while trying to keep a straight face, I solemnly told her it was dead,” Kelly continued.

Queen Elizabeth then looked “horrified” as Kelly approached her with the toy bird in her hand and said, “April Fool.”

“She had only two words for me: ‘You’re sacked.’ I was laughing uncontrollably as her Majesty turned to His Royal Highness and said, ‘Do you know what she has just done to me? Angela has had me!”

After she got over her initial shock, Queen Elizabeth had a good laugh and decided to take the toy back to the UK where it is stored in her private living room.

Queen Elizabeth II
Queen Elizabeth II is seen at the Chichester Theatre while visiting West Sussex on Nov. 30, 2017, in Chichester, United Kingdom. Getty Images/Stuart C. Wilson