REBECCA ENGLISH: When I saw William this week, he looked like he'd the weight of the world on his shoulders. But he's proving what a class act he is

He is a man born into centuries of tradition and steeped in duty – but is a husband and father first.

Time and time again over the years, Prince William has made clear that while he takes seriously the burden of his future role as king and his current responsibilities as heir to the throne, he will never put them before his wife and family.

Those qualities will be needed now, more than ever before.

William has always made clear how proud he is of Kate, both personally and in the way she has embraced her role.

The Prince of Wales and Queen Camilla arrive at the annual Commonwealth Day Service at Westminster Abbey earlier this month 

William attends a meeting in Sheffield this week focusing on ending homelessness in the UK

Indeed not so long ago, while talking to me about his own work, he made a point of bringing her into the conversation, stressing how he would see her sitting in their lounge, night after night, poring over papers relating to her groundbreaking work on children’s early years.

It was abundantly clear he wanted the world to know that she was his equal, and more.

And he has always emphasised that it was Kate who was the brains behind their joint Heads Together campaign with Prince Harry to break the national stigma around mental health.

But more importantly, I would suggest, it is the princess’s grounded brilliance as a mother, and the joy and happiness that she and their family have brought him, that has irrevocably changed William’s life.

He is a child of a broken marriage and warring parents, and grew up in the white heat of the public limelight. Kate’s steadiness, diligence and discretion have been just what he needed as a man.

I don’t think any of us can even begin to understand how difficult the past few months will have been for William.

Just watching what his wife has been going through: The worry of major abdominal surgery, the joyous news that the surgery had been successful, and then the heart-stopping diagnosis that, in fact, cancer had been found.

Add to that his father’s own surgery and subsequent cancer diagnosis... well, that’s a hard load for anyone to bear.

Just this week, I accompanied William on a public engagement to Sheffield to highlight his Homewards project to end the scourge of homeless in the UK.

Afterwards I wrote a commentary in the Daily Mail about how he was on fantastic form with all he met, engaging, enthusiastic, passionate and knowledgable.

But I also wrote about how, having covered the Royal Family for so long, you learn how to read their body language, and it was clear to me that William was also a man with the weight of the world on his shoulders.

I couldn’t quite put my finger on exactly what it was, but there was a slight sadness around the eyes and, noticeably, a loss of weight.

How remarkable that he has even been able to do half of what he has undertaken publicly in recent months – even carrying out investitures for his cancer-stricken father – given everything that has been going on behind the scenes.

And even more remarkable that he was spending the day working to see what he could do for others, knowing that the very next morning he would be at Windsor with his wife as she recorded a moving video message to reveal her cancer diagnosis and the couple’s private plight to the world.

It is also a sign of the solidity of their relationship that both they and their staff were at pains to stress yesterday that their children have been at the heart of everything they have done since January, in spite of the sometimes hideously unbearable provocation they have received, particularly on social media.

Indeed, as aides briefed a small group of journalists, including myself, about the cancer news that they were about to break to the world yesterday, there was not one attempt to finger-point at the gossip-mongers who have caused the prince and princess so much distress in recent weeks.

The fact that the couple have not publicly lambasted the trolls, and instead focused on their children and those who have found themselves in the same, frightening position, shows what a class act they are. 

Several of us asked whether their statement had been issued now to counter those vultures.

And while it was made clear that they hoped that speculation would now end, it was also stressed the announcement was very much being made around the children.

I closed my earlier piece this week for the Mail revealing that I had been told the couple had not entirely ruled out making some kind of public statement in the coming weeks.

There was much William would like to say, I said.

I added that it has been tough for him to stand by and see his wife’s reputation shredded by the court of public opinion in the way his late mother’s once was, and remarked that how he handles the situation moving forwards will surely be a mark of the King he is one day to become.

I think we all know the answer to that now.

He is a man who knows his moral compass and what truly matters to him. He has shoulders broader than anyone imagined.

Those are qualities that we, as a country, one day in the future, will be lucky to share.