Prince Harry: So close and yet so distant King Charles and his son

They may have been little more than two miles apart physically, but the emotional distance between Prince Harry and the rest of the royal family seemed greater than ever on Wednesday.

While senior royals put on a show of unity for the King as he attended the first Buckingham Palace garden party of the summer season, his youngest son arrived alone at St Paul’s Cathedral to mark the tenth anniversary of his Invictus Games.

There were warm – perhaps pointedly so – hugs from Harry for his uncle, Earl Spencer, and aunt, Lady Jane Fellowes, the siblings of his late mother Princess Diana.

And Harry, 39, was certainly in his element among the injured former servicemen and women whose lives his Paralympics-style competition has undoubtedly transformed, and who he often calls his “Invictus family”.

But there were none of his royal blood relatives – with the most notable absentees his father and brother, who so proudly attended the inaugural Invictus event in London at his side in 2014.

While both were busy elsewhere on significant royal duties, it seems that even if their diaries had been clear a reunion was unlikely to have ever been on the cards.

To many this is understandable given the repeated and highly public attacks and accusations Harry has subjected them to over the past three years – not least because of the genuine heartache his actions caused their beloved Queen Elizabeth.

However, some waiting for a glimpse of the Prince outside St Paul’s urged them to let bygones be bygones.

Paul and Amanda Redhead, from Leeds, said the solution to the monarchy’s ongoing issues is simple.

Mr Redhead said: “One of them just needs to step up. They just need to knock on the door and say, ‘Hi. We’ve all had it in our families before.’

“Well perhaps, royal sources have long argued, if his accusations hadn’t been so hurtful, and the spilling of family confidences so spitefully public.

Over at Buckingham Palace, the King (who Harry made clear this week was too busy to see him) had a packed morning of meetings before greeting 8000 guests, who had been invited to the garden party for their service to communities, the military or charities and other organisations at 4pm.

He was accompanied by his wife the Queen, the Duke and Duchess of Edinburgh, the Princess Royal and the Duke and Duchess of Gloucester.

It was a clear sign of solidarity for Charles, 75, who has just been given permission to carry out more forward-facing public duties by doctors amid his ongoing cancer battle.

While he continues treatment, each engagement is being calibrated to balance his desire to meet as many members of the public as possible with his health.

Aides are particularly keen he is protected as much as possible from picking up any colds or bugs.

Although there were thousands of guests present, however, the event was deemed appropriate as it takes place outside on the palace lawn.

The King may have met slightly fewer people than he would do in a normal year but the changes were minimal – and he was clearly delighted to get out and shake as many hands as he could.

After standing on the terrace for the National Anthem, the King was escorted by the Yeoman of the Guard down to the lawn to mingle with the crowds.

Spontaneous applause erupted at the sight of His Majesty as he began to move along his predetermined “lane”, escorted by gentleman ushers in top hats and tails.

“God bless you”, said one man, clasping his hands. “I’ve dreamt of this all my life.”

Another added: “So glad you are looking so much better.”

“I’m not doing badly,” Charles smiled, clearly touched.

Dozens asked after his health and told him how good it was to see him back in public again.

“How are you feeling, Sir?” one man asked.

“Not too bad,” he replied.

Spotting one guest tucking into a plate of cakes, the King joked: “Did you make them yourself? Are you being looked after?”

“Good to see you out and about again,” he was told.

The Queen, meanwhile, appeared touched as one guest told her: “We are thinking of you.”

The couple met up just before they got to the Royal Tea Tent, with Camilla – clearly keen for a cuppa – jokingly ushering her husband on as he continued to chat.

Although there had been expectations the King might cut his visit short slightly, he left not long after 5pm as he normally does.

As he made his way out of the palace garden to prepare for his weekly audience with the Prime Minister followed by a full Privy Council meeting, Harry was arriving at St Paul’s.

A significant crowd had gathered, mostly an opportunistic one, who largely cheered at Harry’s arrival but sounded the odd “boo” too.

The prince waved and headed inside to greet members of the extensive congregation, appearing smiling and relaxed.

Harry listened intently as Damian Lewis gave a theatrical reading of the poem Invictus by WE Henley, and offered his own from Corinthians.

He also appeared emotional as Michelle Turner, vice-captain of Team UK at Sydney Invictus, thanked the competition for “giving me my life back”.

The prince, who remains fifth in line to the throne despite not undertaking any official duties or living in the UK, is due to leave on Thursday, according to reports.

He is set to fly to Nigeria with his wife Meghan, ostensibly to publicise the Invictus Games but on what has also been described as a “quasi-royal tour”.

With his father in Surrey for a military visit and Prince William in Cornwall on official engagements, there will be no time for a last minute change of heart – on either side.

Additional reporting: Natasha Livingstone and Meike Leonard