The hilarious cushion owned by the Queen

Queen Elizabeth II leaves in a car after attending the Easter Mattins service at St George's Chapel. Photo / Getty

She may seem serious while carrying out royal duties, but a UK documentary has revealed the Queen's softer side.

In a scene from the documentary, Our Queen at 90, viewers got a rare, behind-the-scenes glimpse of the Queen's private living room at Balmoral Castle.

The brief shot revealed a humorous cushion sitting on a table, embroidered with the message "It's good to be Queen."

The Queen has the best cushion 😅 #itsgoodtobequeen #hrh #itv #ourqueenat90 pic.twitter.com/pSHQOfXjgX

— Geraldine Carr (@GeriCarr) March 27, 2016

Royal-watchers were quick to share an image of the cushion on social media, to the delight of Twitter users around the world.

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A new book has also recently highlighted the quirks of the royal family. In Thomas Blaikie's, What A Thing To Say To The Queen: A Collection Of Royal Anecdotes From The House Of Windsor, it's revealed the Queen collects pepper grinders.

According to the book, one of her favourite pepper grinders was purchased from an Italian restaurant, and resembles a waiter. When the head is turned to release the pepper, the waiter shrieks, in a heavy Italian accent, "You're breaking my neck!". The grinder was a gift from a friend, and the Queen is said to find it most amusing.

The book also details the importance of the Queen's handbag. Said to contain a range of good luck charms from her children, including miniature dog and horse figurines, the Queen apparently places it on a table to signal she wishes to leave in five minutes. When she switches the bag from arm to arm, it means she needs to move on and speak to someone else.

- NZ Herald