Kensington Palace surprised royal fans by sharing an old photo of Prince Harry, Prince William, Princess Diana, Zara Tindall and Peter Phillips yesterday.
The Kensington Royal Instagram account included the photo in a post about 999 Day - which celebrates the Police, Fire and Emergency Medical Services in the United Kingdom.
The post also featured several photos of the Duke of Cambridge speaking with various emergency professionals.
However, the royal family pulled at the heartstrings of their followers by placing the throwback photo at the front of the post.
In the image (which was from 1988) Princess Diana could be seen looking on as her children Prince William and Prince Harry played with their cousins Peter Phillips and Zara Tindall on a fire truck from the Old Fire Station in Sandringham.
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"The first photograph in this post is of The Duke of Cambridge and The Duke of Sussex and their mother Diana, Princess of Wales, with their cousins Peter Phillips and Zara Tindall in the yard of the Old Fire Station 🚒 in the grounds of Sandringham House in 1988," the caption read, followed by an announcement that the Duke of Cambridge would be visiting the Firefighters Charity at Harcombe House in Devon later that day.
See the post below:
The Daily Mail reported that his Royal Highness is expected to hear about the support the Firefighters Charity provides to members of the UK's fire and rescue services and their families.
The publication also said that the Duke will meet representatives from the wider emergency services community during the visit to mark Emergency Services Day.
According to the Instagram post, Prince William made the following statement about the emergency services: "As a society, we owe our wellbeing, and indeed our lives, to the men and women in our emergency services who work tirelessly to protect us in some of the most difficult circumstances.
"It is only fitting that we should recognise the vital role that they play, and pay tribute to the bravery and dedication of those who have made the ultimate sacrifice for their communities."