George, Charlotte and Louis make first ever social media post to commemorate William on Father’s Day

Prince George, 10, Princess Charlotte, 9, and Prince Louis, 6, had a very special message for their dad, Prince William, to celebrate Father's Day.

The three young royals shared an adorable picture taken by their mum, Princess Kate, on social media to mark Father’s Day in the UK.

Along with the image, in which the Wales children can be seen hugging their dad as they look out towards the ocean, the children wrote: “We love you, Papa. Happy Father’s Day.”

While the Wales children are often seen in photos and videos shared on Kensington Palace’s social media channels, it is the first time a message has been signed off with “G, C & L”.

The Daily Telegraph has reported the photo was taken last month at a beach in Norfolk, apparently when the children were on school holidays.

William also had a special message for his father, King Charles today and shared an old photo of the pair from when William was just a young boy in 1984.

Alongside a photo of himself as a toddler wearing a striped T-shirt and blue overalls, the 75-year-old monarch’s eldest son captioned the post: “Happy Father’s Day, Pa. W.”

It comes just one day after the royal family put on a united front as they attended Trooping the Colour - a celebration of Charles’ birthday.

The occasion was made even more memorable as it marked the first time Princess Kate had made a royal appearance in more than six months.

Kate is currently undergoing cancer treatment and revealed on Friday, just one day before the annual event was due to take place, that she would be making her long-awaited return to the public eye.

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Despite her attendance, Palace aides were quick to state the announcement does not mean the mother of three is returning to public duties but will attempt to partake in some engagements over the northern hemisphere’s summer.

Thanking the public for their messages of support, Kate said in her statement: “It really has made the world of difference to William and me and has helped us both through some of the harder times,” she said.

She finished by saying: “Thank you so much for your continued understanding, and to all of you who have so bravely shared your stories with me.”

It was widely reported that Kate attended Trooping the Colour so that her three children would not have to ride in a carriage without an adult.

She appeared in good spirits as she stood on the Buckingham Palace balcony along with her children, William, King Charles, Queen Camilla and other senior royals.

- Written by the NZ Herald and republished here with edits and permission