Prince William shares adorable throwback photo of him and Prince Harry with Princess Diana

Publish Date: Tuesday, 10 September 2019, 9:49AM

It seems Prince William has been feeling a little nostalgic and had a look back through his old family photo album ... and came across the perfect snap to share before stepping out to launch a texting service aimed at helping first responders yesterday.

In honour of 999 Day in the United Kingdom - a special day commemorating those who work in the emergency services - the Duke of Cambridge took to his official Instagram account to post a photo from 1988 of himself and Prince Harry on a fire truck, as their mother lovingly looked on, in the grounds of Sandringham House.

And precious is an understatement!

Dressed in matching pale blue coats and gold firefighter helmets, the two Princes can be seen posing on the vintage fire truck during a playdate with their cousins, Peter and Zara Phillips.

"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 reads.

View this post on Instagram

Today marks #999DayUK, when we celebrate and say thank you to our incredible Police, Fire and Emergency Medical services 👮‍♀👨‍🚒👩‍⚕ and all our specialised emergency services for all that they do to keep us safe. 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. On 999 Day later today The Duke will visit @TheFirefightersCharity at Harcombe House in Devon to hear about the support that the centre provides to members of the fire and rescue service and their families, and meet representatives from across the emergency services sector. On the extraordinary work of our emergency services, The Duke of Cambridge said: "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." 999 Day begins annually at 9am on the 9th September (the 9th hour of the 9th day of the 9th month) and is held to pay tribute to the invaluable work that is carried out by the emergency services and responders. 📷 Getty images / Press Association

A post shared by Kensington Palace (@kensingtonroyal) on Sep 9, 2019 at 2:42am PDT

"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," William said in a statement shared on Instagram. "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."

In the photo, the late Princess Diana is wearing a beret over her short blonde locks, while watching her kids and their cousins playing on the truck.

And fans were, of course, overjoyed to see the photo of the "People's Princess".

"Beautiful photo in memorial to a more innocent time, when Diana looked over her boys and all was harmonious in their young world," wrote one follower.

While another person commented on how touching it was to see a photo of Diana on the Kensington Palace Instagram.

"It's the first time I've seen a picture of Prince William and his loving mother together on this profile, and it's quite humble and moving," they said.

Without a doubt, Princess Diana would be incredibly proud of the men her sons have become.

The additional photos in the post are of Prince William speaking with men and women of the police force, as well as from fire and emergency medical services.

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