INGRID SEWARD: Prince Philip will be turning in his grave after Harry ignored his wishes and essentially abandoned his family name

There are undoubtedly good reasons for Harry and Meghan to take 'Sussex' as their surname.

Perhaps, as Meghan has suggested, it will “unite” her family, although I'm not sure how. “Unite” is not a word I particularly associate with Montecito.

Perhaps it keeps things clean and simple in brand-conscious America, where the finer points of aristocratic titles are little known or understood.

But in the world of the British royal family – where dukedoms have their origins – things are a little different. There are rules for those who inherit or receive these privileges.

(The title Duke of Sussex was a gift from the prince's grandmother, Queen Elizabeth, on Harry's wedding day in 2018.)

And I fear that this is a step that will only lead to the prince and his children further distancing themselves from the royal family, from their British roots, and from a father and grandfather, the king, who now has cancer. established.

There is a distinction to be made here. I don't all object to Harry using Sussex as his surname.

After all, there's a history to that kind of thing. Consider, for example, Princess Margaret's husband, who was given the title Earl of Snowdon after his marriage to the Queen's sister.

He used the name Tony Snowdon completely legitimately, both socially and professionally.

As the wife of a royal duke, it is perfectly acceptable for Meghan to call herself Meghan Sussex. Why not?

But for the children, four-year-old Archie and Lilibet, two, it's different.

Their family name is Mountbatten Windsor – and it should remain that way. 'Sussex' is incorrect. It's not even a last name.

Few Americans will be much concerned by all this – and it's hard to avoid the suspicion that the US is the only place registering with Meghan.

Yet the royal family cares about these things, and so does the British public.

Moreover, the surname Mountbatten-Windsor has a special meaning.

Philip was dismayed to discover that when his wife, Princess Elizabeth, became queen in 1952, their children – and their children's children – would not bear his surname, Mountbatten.

They would rather be Windsors, named after the queen's family.

Philip was both furious and wounded. The decision was perceived as discouraging and cruel.

“I am the only man in the country who is not allowed to give his name to his children,” he protested.

“It hurts him,” recalled Countess Mountbatten at the time, wife of Philip's uncle and mentor, Lord Mountbatten of Burma.

'He had given up everything for his wife and this was the final insult. It was a terrible blow.'

It was the elder statesman Winston Churchill who found a solution, encouraged by the young queen's private secretary, Tommy Lascelles – a wise head some forty years her senior.

Together, Churchill and Lascelles forced Elizabeth's hand – she lacked the confidence to do it herself – and it was agreed that all descendants of the royal couple along the male line would be called Mountbatten-Windsor, apart from those who were princes and princesses.

A tactful compromise.

How sad, then, that just three generations later, Harry so blatantly ignored his grandfather's wishes and effectively abandoned the family name Philip had fought for.

Harry claimed to respect and love the Duke of Edinburgh and I am sure he did and always will, but this latest debacle would make Philip turn in his grave.

Do Harry and Meghan think they are smart? Perhaps this is an attempt to entrench the Sussex name so firmly that, regardless of the political atmosphere in Britain, the title can never be effectively removed.

Maybe they're just being poorly advised.

But it's hard to avoid the suspicion – as it has been from the start – that the Duke and Duchess of Sussex want everything to be right.

Be royal – but in a style of your choice. To have the status and at the same time have free rein to choose the obligations that come with that status.

Changing their surname can only be a provocation to Harry's father at a time when he has more pressing matters to think about.

Of course, there is little the king can do without appearing rude. He will feel that he has no choice but to turn the other cheek, as he has long done, even though forbearance often comes at a significant mental cost.

Saddest of all, I'm sure Prince Harry still loves his family and hopes in his heart for a reconciliation.

But again, he pushes them away.

• Ingrid Seward is the author of My Mother & I – the relationship between Charles and the late Queen, published by Simon & Schuster