By Deborah Arthurs and Rebecca English

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He has described her as the sister he never had. Once again yesterday Prince Harry and the Duchess of Cambridge demonstrated the closeness of their friendship as they smiled and giggled their way through the royal balcony appearance.

While Kate’s husband Prince William stood formally, hands clasped, his cheeky brother whispered a series of humorous asides to his sister-in-law.

Kate was equally gregarious, constantly leaning towards Harry to share with him her own observations.

Kate whispers in Harry's ear before the service

Kate whispers in Harry's ear before the service

The Duchess smiles at one of Harry's asides

The Duchess smiles at one of Harry's asides

More laughs on the palace balcony

More laughs on the palace balcony

If there is one thing that this Jubilee weekend has proved apart from the nation's renewed passion for the Monarchy it has been how warmly Kate has been welcomed into the heart of the Royal Family.

The scenes of innocent fun were a reminder of Harry’s teasing of Kate’s sister, Pippa, following last year’s royal wedding which led to ill-founded rumours of a royal romance.

Kate and Harry also chatted yesterday as they rode in an open-topped carriage together and at the service of thanksgiving at St Paul’s Cathedral where they put their heads together and whispered as they waited for the Queen.

William adopts a formal pose on the balcony while his wife and his brother keep up the banter

William adopts a formal pose on the balcony after the service of thanksgiving at St Paul's Cathedral while his wife and his brother keep up the banter

Harry's repartee with Kate recalls his flirting with her sister Pippa at William and Kate's wedding last summer

Earlier this year the Daily Mail revealed how Harry had moved near to William and Kate at Kensington Palace, living in a one-bedroomed flat close to their home, Nottingham Cottage.

The three young Royals are all utterly at ease in each other's company.

On the balcony of Buckingham Palace yesterday afternoon, with Kate's role as a senior royal cemented thanks to the depth of her involvement in the Jubilee weekend celebrations, the affection the two share was more evident than ever, as they cracked jokes and shared asides during the fly past.

To their right, despite joining in the revelry throughout the weekend, now a more serious William had one eye on his duties. Standing next to his grandmother on this auspicious occasion there can be no doubt the Duke of Cambridge's mind would have strayed to the prospect that he would, one day, be standing on this very spot as King.

Still, William found the time to set the gravitas aside from time to time, sidling over to his brother and wife to join in the fun.

On the way back to Buckingham Palace the three had shared a carriage and looked to be having a whale of a time as they waved to the throngs lining the streets.

That morning, the three had sat in silent solidarity in St Paul's, looking rather worse for wear after the previous night's revelry at the Buckingham Palace Jubilee concert, where they had sung along and waved Union flags from the royal box.

This affection for Kate, and the ease in which all of the Royals have accepted their newest member into their ranks, made her path from newlywed to senior royal all the more smooth.

Gazing upwards: The family stare and gasp in delight as the Red Arrows zoom overhead

Modern face of the family: The royals have been careful to welcome Kate into the heart of the family to avoid her suffering the isolation felt by Diana

Modern face of the family: The next generation of royals beam as they admire the impressive show along with 1.5m people across London

Good friends: William and Kate spend lots of time socialising with Harry, and the three are firm friends

Lightening the mood: Prince William looks rather sombre as Harry shares a joke with his sister-in-law, the Duchess of Cambridge

Lifting the mood: Prince William chuckles along as his fun-loving brother Prince Harry shares a joke with his sister-in-law

Lost in thought: A serious-looking Prince William stands slightly apart from his cheerful wife and brother as he surveys the awe-inspiring scene

Lost in thought: With his duties as future King perhaps weighing on his mind, Prince William looks pensive as he surveys the awe-inspiring scene from the balcony

Given Diana, Princess of Wales' sense of isolation and difficulty in adjusting to her new role as a Royal and the fallout which ensued, the Queen and William were said to be adamant that Kate's trajectory would be very different.

And it has been thus. Not only has Kate received the Queen's royal seal of approval, but she has enjoyed private suppers and opera visits with Prince Charles, and been privy to personal advice doled out to her by a supportive Camilla in meetings the two have had together.

At public engagements, Kate is frequently seen laughing uproariously with Camilla, or chatting earnestly with Charles. She has proved to be an asset to the royals - and has been largely behind the world's renewed interest in, and fondness for, the royal family.

She has found her niche in the royal family with ease, thanks to her natural warmth and the support offered to her by her new in-laws. And if the images from this weekend's celebrations are anything to go by, it looks as though they are as pleased to have her as she is to have them.

A royal source said: ‘Prince Harry adores his brother and says Catherine is the sister he never had.’

That's enough now: The Duke of Cambridge looks miffed as Harry continues to chat with his wife while he stands to the side

Deep in conversation: The Duke of Cambridge watches the fly past as the Duchess of Cambridge and Harry share a conversation

Enjoying the moment: Fun-loving Prince Harry kept up a running commentary as he entertained the Duchess of Cambridge with jokes and observations

Roadtrip! The Duchess of Cambridge, Prince William and Prince Harry make the most of the carriage ride back to Buckingham Palace after the lunch at Westminster today

Road trip! The Duchess of Cambridge, Prince William and  Prince Harry make the most of the carriage ride back to Buckingham Palace after the lunch at Westminster today

All smiles: The young royals beam and wave, clearly enjoying the ride

All smiles: The young royals beam and wave, clearly enjoying the ride

Composed: Kate looked the epitome of ladylike elegance at the service this morning

Composed: Kate, sat between a rather tired-looking William and Harry after last night's revelry, looked the epitome of ladylike elegance at this morning's service in her Alexander McQueen dress

Close: Kate leans in to chat to Harry, who looked to be suffering slightly from the effects of a later night during the service

Close: Kate leans in to chat to Harry, who looked to be suffering slightly from the effects of a later night during the service

A more formal setting for the prince and the Duke and Duchess of Cambridge after the Jubilee concert last night

The Stooges suffer! A more formal setting for the prince and the Duke and Duchess of Cambridge after the fun of the Jubilee concert last night

After a weekend of duties, the young Royals let loose at last night's Jubilee concert, where they waved flags and sang along to performances

It's party time! After a weekend of duties, the young royals let loose at last night's Jubilee concert, where they waved flags and sang along to performances by Paul McCartney, Elton John, Jessie J and Kylie Minogue (l-r) Princess Beatrice, Duchess of Cambridge, Duke of Cambridge, Prince Harry

Great show: Kate looked delighted to be part of the electric atmosphere

Great show: Kate and William looked delighted to be part of the electric atmosphere and William, who must have felt the weight of the future on his shoulders over this auspicious weekend, appeared to truly relax during the show

Sharing a joke: William and Harry were in high spirits at the concert

Sharing a joke: Not for the first time, William and Harry were in high spirits at the concert, which saw the senior Royals and younger members of the family come together in a jubilant celebration


Here's what other readers have said. Why not add your thoughts, or debate this issue live on our message boards.

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I've been saying this for a while. Wills' eyes have opened and he sees he was conned into marrying this Middleton girl. He is highly irritated by her. They are barely talking. His recent hunting trip to Spain with just Harry was a 'family summit' to discuss his predicament. Harry, his closest confidante is very practical and would have said, 'Bro. ....it's too late - you have to live with it'. He felt he had to hurry things along last year because of the jubilee since the Middletons were effectively giving him an ultimatum. They'll probably drag it on for as long as they can and the curse of the Windsors will strike again. He should have dated other women before committing to marriage but was he given any chance by the Middleton's vicious tenacity?

when ur unloved & constantly ignored in public by ur husband, looking like the unentitled outsider that u are @ these dos, then theres very little else 4the girl to do but to pretend at conversation with the nearest fall guy.its only ever harry or camilla. another "look involved & popular" technique is rudely pointing into ur face, Dianas ring 2camera, then laughing, gop open, like shes at an "Omen" audition...cos what you said about the weather was just like soooooooooooooo funny

Its so good to see Kate and Harry sharing jokes and laughter. He seems like a down to earth guy

If we didn't know she was married to Prince William, we could thing that she is married to Prince Harry ! I love their brother/sister in law relashionship however...

I'm just guessing but I got the feeling at the flotilla procession that, by their body language, they had had a wee tiff. It seemed to carry on into the next days and she was perhaps trying to needle him with the flirting with his brother. I wouldn't read too much into it, yet, couples fall out and do these stupid little things. The fact that lots of us noticed it, including the press, perhaps means that someone needs to have a little talk. - Dee, UK, 6/6/2012 11:19.......I formed the same opinion Dee.......and whereas you say...couples do fall out.....if you're a Royal you have to be professional and not let it show in public...you have to put on a united front......but sometimes their expressions and the distance between them reminded me very much of Charles and Diana when their marriage was beginning to break up...and I can't see this marriage lasting either.....if they do break up then better sooner than later before any children come along......it will be less complicated

Pehaps we are reading too much into situation, but it just looks and feels uncomfotable to watch, especially in front of the public.

Kate's behaviour was quite Fergie like yesterday. I can't be the only one who thought oh no not again!

For some reason during these past few days, William and Kate have been distant. I think Harry was trying to lighten the mood and to make up for his brother by some banter between him and Kate. Nothing more. They didn't want to make it obvious to the Queen. Harry has a jovial personality and it makes him attractive to women, not least Kate. Though I do think William, whatever mood he is in, should have bluffed his way through the weekend and Kate should have stood by her husband, regardless of how they both feel. As a result articles like this will rear their ugly heads.

It looked very much as though William and Kate had had a row, there was no closeness between them at all!

We all know people that we can have a laugh with but we'd never marry them. Harry and Kate get on really well which is good. Harry isn't flirting, Harry is just being Harry !

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