Queen Elizabeth II and her corgis are inseparable, so much so that the British monarch writes letters on behalf of her beloved pets.

The Queen wrote a series of "wickedly funny" letters to the palace staff member's dogs from her corgis, as revealed in a new ITV documentary "The Queen and her Cousins." English actor Alexander Armstrong, who is presenting the documentary, said that he found these handwritten notes framed in the bathroom of Sir Blair Stewart-Wilson, former equerry to the Queen, reports The Telegraph.

"He would write these letters from their Jack Russell to the corgis, and the Queen would write these letters back. And they put this series of letters up, and they are so funny. I wish I could remember them," Armstong recalled.

The television presenter added that the notes were so "wickedly funny" that he had to hold his stomach while "howling with laughter."

The queen is known for her love of corgis and dorgis, who have accompanied her throughout her reign. In a skit for the opening ceremony of the 2012 London Olympics, it was her corgis named Willow, Monty, and Holly, who led James Bond (played by Daniel Craig) when he arrived at Buckingham Palace to accept a mission from the Queen. Though the 94-year-old has numerous staff members to tend to most of her needs, she likes to feed the corgis herself and takes them on their daily walks.

The monarch recently added two new puppies to the family: a dorgi called Fergus, named after her late uncle who died during World War I in 1915, Fergus Bowes-Lyon, and a corgi called Muick, named after Loch Muick, a loch located within the boundary of her beloved summer escape, Balmoral estate in Scotland.

The queen's private life and fun side are explored in the new documentary "The Queen and her Cousins," which will air on Thursday, April 15, to mark the monarch's forthcoming birthday on April 21. The programme will feature Armstrong travelling across the UK to interview some cousins of the queen about their most famous relative and what it's like to be part of the royal family.

Queen 90th birthday
1974: The Queen arrives at Aberdeen airport with her corgis to start her holidays in Balmoral. Her handbag by British brand Launer and handmade shoes by Anello and Davide of Kensington have remained the same style for over 50 years, whilst more contemporary additions such as the feather headpiece are typically 1970's. Anwar Hussein/Getty Images
Queen Elizabeth II British Royal Family Prince Philip