Prince William and Kate, the Princess of Wales, shared a photo on social media of the queen posing with 10 of her grandchildren and great-grandchildren.
The photo was taken by Kate last summer at Balmoral Castle, the queen's estate in Scotland, according to Kensington Palace.
The queen died last September while staying at Balmoral.
At the time of her death at age 96, the queen was a grandmother of eight and great-grandmother of 12.
Among the children pictured in the photo with the queen are Princes George and Louis and Princess Charlotte, the children of William and Kate, as well as the queen's two youngest grandchildren, Lady Louise Windsor and James, Earl of Wessex, the children of Prince Edward and Sophie, the Duchess of Edinburgh.
In addition to the remembrance from William and Kate, the queen's eldest son King Charles III and his wife Camilla, the Queen Consort, also remembered the queen.
In a post on the royal family's official Twitter account, they wrote, "Today we remember the incredible life and legacy of Her Majesty Queen Elizabeth II, on what would have been her 97th birthday."
Charles' and Camilla's coronation will be the first since 1953, when the queen was coronated at Westminster Abbey.
Last May, several months before her death, the queen celebrated her Platinum Jubilee, marking 70 years on the throne.