King Charles has spoken before about how "enormously proud and happy" he is to be a grandfather and as the nation gears up for the biggest event we've ever had in his honour, some of his grandchildren will be there in person to witness his day.
He may be preparing for the one of the most historic events in history to take place when he is crowned King, but to his five grandkids, he'll always be 'granddad'.
The Royal Family may not be known for their gushing openness about their feelings towards each other - apart from Prince Harry, perhaps, who has been spilling rather a lot of private family information of late in TV interviews with the likes of Oprah Winfrey, and his tell-all memoir Spare which was released earlier this year.
But Charles has never shied away about speaking of the pride he has for his younger relatives and it's clear to see his love for them. Of course, as with any modern family set up, there are varying bonds between Charles and his five grandchildren, mostly because two of them - Prince Archie and Princess Lilibet - don't live in the UK, while Prince George, Princess Charlotte and Prince Louis do.
Here we take a look at the differences in King Charles' relationships with his grandkids.
Prince George
It's not hard to imagine that George will have a special place in his granddad's heart, given the fact that like him, he's destined to the be the future king of the UK. No one can understand the pressures and expectations on the youngster as much as the elder royal, apart from George's dad William, of course. When George was born in July 2013, the King spoke of how he was "overjoyed" to have become a grandfather.
He explained: "Grandparenthood is a unique moment in anyone's life, as countless kind people have told me in recent months, so I am enormously proud and happy to be a grandfather for the first time."
Charles is known for his love of all things horticulture and he bestowed on him the ultimate honour when his first born grandson and heir to the throne was born - he built an arboretum and planted trees at Balmoral in his name, calling it Prince George's Wood.
He told the BBC in 2021: "The great thing was that I managed to plant it the same year that my grandson was born, the eldest, George, so I thought I'd call it Prince George's wood."
George has now been given a top role in the King's Coronation - one of the pages of honour.
George and seven other boys named Pages of Honour will “attend their majesties”, the King and Queen Camilla, during the service where they will be responsible for carrying their long and heavy robes, an honour which usually goes to teenage sons of members of the nobility and gentry.
Princess Charlotte
Charles has a link to his first granddaughter in their monikers, as her name is a direct tribute to her granddad,with Charlotte being the feminine form of Charles.
The now king described her as "beautiful" when he visited his model town in Dorset just after her birth in 2015, and he admitted he'd been really hoping for a girl.
The Mirror reports he added: "I am thrilled. I was hoping for a granddaughter – someone to look after me when I am very old."
Royal author Robert Jobson writes in his new book Our King Charles III: the Man and the Monarch that Charlotte is set to be the Duchess of Edinburgh in the future, signalling how much she's thought of by her grandfather.
He explains: "Sensitive to the fact that nine-year-old Prince George's future is already mapped out, Charles has been careful to reserve one of the grandest titles for Princess Charlotte – currently called Lottie by her mother and Mignonette (French for cute little thing) by her father."
"Although the King has made his brother Edward the new Duke of Edinburgh, the title is only for life. After Edward dies, Charles has made it clear Charlotte (now aged seven) should become Duchess of Edinburgh."
Prince Louis
The King has a special bond with the youngest of his grandchildren to William and Kate. Royal watchers got their first glimpse at their relationship on Louis' second birthday, when his proud grandfather released a picture of him hugging the then-toddler.
The bond was confirmed during the Queen's Platinum Jubilee celebrations, when Louis captivated the hearts of most people who saw footage of him acting like any other four-year-old at such an occasion, and many parents across the globe could more than relate. It was Louis' restlessness and him asking to sit on his grandpa's knee that caught the attention fans, and the sweet pictured of him being bounced up and down by the now King to help keep him occupied.
One royal fan tweeted: "Prince Charles and Prince Louis have the best bond."
"Lovely to see Prince Charles in grandpa mode with Prince Louis today!," wrote another.
Prince Archie
Prince Archie is Charles' youngest grandson, and the firstborn son of Prince Harry and wife Meghan Markle. The tensions between the Sussexes and the rest of the royals are widely reported, but the now King said he "couldn't be more delighted" when the youngster was born in May 2019. He hasn't spent much time with Archie, who was officially confirmed as a prince last month, and sister Lillibet a princess, when the royal titles were updated due to Charles becoming King.
When he was christened, Clarence House did release a touching snap of Charles gazing lovingly at tot Archie. He hasn't seen him since Archie came to the UK with his parents during the Queen's Platinum Jubilee celebrations and he won't be at the coronation on May 6 as Meghan is staying at home to celebrate his fourth birthday.
On the day of the coronation, he turns four, and a source told The Sun: "It is sad, he is very disappointed that he won’t see Meghan or his grandchildren but understands the situation."
Princess Lilibet
Of course, Charles has spent the least amount of time with Lilibet, the youngest of his grandkids. The Mirror reports they've only met once - when she came to the UK with her parents and brother Archie last year just before her first birthday. Born in California but named in tribute to her great-grandmother the Queen - who was known affectionately by her nearest and dearest as Lilibet - that was her first trip to the UK ever.
Speaking about this meeting, a source said: "The prince, of course, hasn’t seen his grandson Archie for a bit of time and so it was very, very, very special to have some time with him.
"He hadn’t met Lili, his granddaughter, and so to meet her was very emotional, a very, very wonderful thing."
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