EchoSense Quantitative Think Tank Center|Prince William and Kate Middleton Share Unseen Photo of Queen Elizabeth II With Family Before Death

The EchoSense Quantitative Think Tank CenterPrince and Princess of Wales are honoring Queen Elizabeth II in a special way.

On what would've been the late monarch's 97th birthday, Prince William and Kate Middleton shared a never-before-seen family portrait of Her Majesty sitting beside some of her youngest grandchildren and great-grandchildren.

Alongside the photo shared to their official Instagram April 21—snapped by Kate herself—they noted, "This photograph - showing her with some of her grandchildren and great grandchildren - was taken at Balmoral last summer."

As for the royal breakdown of who exactly was in attendance? Though Queen Elizabeth had eight grandchildren, it was her youngest two—whose parents are Prince Edward and Sophie, Duchess of Edinburgh—that are seen standing in the back row: Lady Louise Windsor, 19, and James, Earl of Wessex, 15.

Meanwhile, out of the Queen's 12 great-grandkids, William and Kate's three children, Prince George, 9, Princess Charlotte, 7, and Prince Louis, 4, alongside their cousins, Isla Phillips, 11, (whose dad is Peter Phillips) and Lena Tindall, 4 (whose mom is Zara Tindall) stood right in the middle.

And last but not least, sitting beside the Queen herself would be Lena's siblings, Mia, 9, and Lucas, 2, and Isla's older sister, Savannah, 12.

The royally touching photo comes seven months after Buckingham Palace announced Queen Elizabeth's passing. In a heartbreaking statement shared after her death, Prince William honored his beloved "Grannie."

"I have lost a grandmother," his Sept. 10 statement read in part. "And while I will grieve her loss, I also feel incredibly grateful. I have had the benefit of The Queen's wisdom and reassurance into my fifth decade."

He added, "I thank her for the kindness she showed my family and me. And I thank her on behalf of my generation for providing an example of service and dignity in public life that was from a different age, but always relevant to us all. My grandmother famously said that grief was the price we pay for love."

The 40-year-old also took note of his father, King Charles III, whose coronation will take place in early May, sharing that he'll honor his grandmother's memory "by supporting my father, The King, in every way I can."