Kate Middleton had one unforgettable wedding anniversary.

Queen Elizabeth II named her granddaughter-in-law as a Dame Grand Cross of the Royal Victorian Order, which is considered the highest possible rank for a British royal, People magazine reported Monday.

The honor came on the eighth wedding anniversary of Middleton and her husband Prince William and just weeks after the two women stepped out for their first-ever joint outing to visit King’s College’s Strand campus in London.

PRINCE WILLIAM, KATE MIDDLETON VISIT PREGNANT MEGHAN MARKLE

Britain's Prince William and Kate, Duchess of Cambridge with their children Prince George, right, Princess Charlotte, center, and Prince Louis.

Britain's Prince William and Kate, Duchess of Cambridge with their children Prince George, right, Princess Charlotte, center, and Prince Louis. (Matt Porteous/Kensington Palace via AP)

Middleton, 37, became a member of the British royal family when she married William, 36, in 2011. William is the queen’s grandson and second-in-line to the throne. The couple share three children: Princes George and Louis and Princess Charlotte.

According to the magazine, the Royal Victorian Order was created by Queen Victoria in 1896 to allow her to recognize people who helped her or represented her. The ruling monarch personally selects who is given the honor.

Previous Knights and Dames Grand Cross include Elizabeth’s sons Prince Andrew and Prince Edward, as well as Camilla, Duchess of Cornwall. People reports the position of Grand Master of the Order was created in 1937 and was occupied by the Queen Mother until her death in 2002. Elizabeth, 93, then appointed her daughter, Princess Anne, to the spot in 2007.

PRINCE HARRY STEPS OUT WITH KATE MIDDLETON

Members of the royal family, including Camilla Duchess of Cornwall, Prince Charles, Catherine, Duchess of Cambridge holding Princess Charlotte, Prince George, Prince William, Queen Elizabeth, and Prince Philip watch a flypast as they stand on the balcony of Buckingham Palace after the annual Trooping the Colour ceremony on Horseguards Parade in central London, Britain June 11, 2016. Trooping the Colour is a ceremony to honour Queen Elizabeth's official birthday. The Queen celebrates her 90th birthday this year.   REUTERS/Toby Melville  - LR1EC6B0ZDPHA

Members of the royal family, including Camilla Duchess of Cornwall, Prince Charles, Catherine, Duchess of Cambridge holding Princess Charlotte, Prince George, Prince William, Queen Elizabeth, and Prince Philip watch a flypast as they stand on the balcony of Buckingham Palace after the annual Trooping the Colour ceremony on Horseguards Parade in central London, on June 11, 2016.  (REUTERS/Toby Melville)

The queen’s husband, Prince Philip, was previously made a Knight Grand Cross of the Royal Victorian Order in 2017, on the couple’s 70th wedding anniversary. Prince Harry was named a Knight Commander of the Royal Victorian Order in 2015.

Royal expert Rebecca Long recently told Us Weekly the queen has been preparing the Duchess of Cambridge for her most important role — becoming the future queen of England.

“Kate’s been taking on new responsibilities little by little over the last few years, so it won’t be a shock when the time comes,” Long explained. “William and Kate are the favorite royals to take the crown in many generations, so the people of the UK are very excited about it.”

According to palace sources, the reigning monarch is determined to show Middleton how to settle into her future title gracefully in the public eye.

Britain's Prince William and his wife Catherine, Duchess of Cambridge, arrive for a Heads Together event to celebrate World Mental Health Day, at County Hall in London, Britain October 10, 2016. REUTERS/Stefan Wermuth  - D1AEUGDXTAAA

Prince William and his wife, Duchess of Cambridge Kate Middleton. (Reuters)

KENSINGTON PALACE RELEASES NEW PHOTOS OF PRINCE LOUIS

“She’s really taken Kate under her wing,” a source close to the royal family told Us Weekly. “The two of them will often spend hours discussing royal life and the future of the monarchy.”

“It’s taken a long time for Kate to get to where she is today,” added a second insider. “But she’s ready.”

Harper’s Bazaar recently reported William and Middleton recently traveled to Frogmore Cottage where Meghan Markle is on maternity leave to spend Easter Sunday with the Duke and Duchess of Sussex. A source told the outlet William and Middleton made their way to the Windsor home shortly after attending church services with the queen at St. George’s Chapel at Windsor Castle.

Britain's Catherine, Duchess of Cambridge, Prince William, Duke of Cambridge, Meghan Markle and Prince Harry leave St Mary Magdalene's church after the Royal Family's Christmas Day service on the Sandringham estate in eastern England, Britain, December 25, 2017. REUTERS/Hannah McKay - RC117DF76700

From left to right: Duchess of Cambridge Kate Middleton, Prince William, Meghan Markle and Prince Harry. (Reuters)

The source claimed that they made the visit in order to keep spirits high given that Markle, 37, was unable to attend the holiday service.

The former American actress is expected to give birth to her first child with Harry, 34, any day now.