- By David Williams, ITV News Content Producer
Prince Harry's marriage to Meghan Markle sees the royal couple join a select group of couples who have found love over the Atlantic.
They have the benefit of a shared language and linked history, alongside the historical tight connections between Downing Street and the White House.
But how will Meghan adapt to London life after LA and can Harry cope with things getting lost in translation?
Three British and American couples tell ITV News what delights and frustrates them - and what they believe makes their relationships that little bit more "special" than others.
Like Meghan, Isha Sodhi made the move from Los Angeles to London when she married London-born Jag in 2001.
The first shocks came when she thanked a cashier personally from his name tag - "he was mortified" - and later was left holding onto a petrol pump in the rain - "in the US we just click a button!".
But after 17 years, the 44-year-old marketing operations specialist delights in her London life, is still thrilled by her husband's accent and has learned to love his "dry sense of humour".
Her diet has changed too.
"I've now accepted that fish fingers and beans on toast are acceptable dinner options," she told ITV News.
"British hot desserts are the best in the world. Custard, sticky toffee pudding, treacle, what's there not to love?"
Quite a bit, according to Dana Fisher.
She's been in the UK for 18 years but the Minnesotan still can't adapt to the British desserts.
"I'm sorry, I can't get my head around custard and your sponge puddings, she told ITV News.
"Your puddings are not our puddings. We have pie, we have ice cream, we have cookies and cake."
Husband Mark is left unimpressed: "She makes a cake for pudding. That's afternoon tea."
Dana replies: "It's not, it's pudding."
Their marriage, which began when Dana made Mark's birth city of London her permanent home in 2000, has been an education for both of them.
"I actually didn't like America or Americans until I met Dana," Mark admits.
The biggest net benefit for the IT manager is his new "circle of American friends" and the personal revelation that "some of them are very nice people!"
For Dana, a 39-year-old healthcare executive assistant, 59-year-old husband Mark represents her British ideal.
"He really is a prince charming," she said, describing him as her "Hugh Grant" or "Benedict Cumberbatch".
In return, Dana says, "He's been teaching me how to be a lady."
Like Meghan, she had to quickly learn about the monarchy - including toasting the Queen on Christmas Day - though the nuances of the British political system still fox her.
But Mark too has had to make compromises.
He says he's accepted her swearing - "that's what Americans do" - and has even grown fond of her "discreet" shoulder tattoo.
Heather Williamson, who grew up in Massachusetts, also swapped the LA sunshine for the near-eternal grey skies of the British capital nine years ago.
She met Abergavenny-born Simon Assender at a party at the end of the 2012 London Olympics. The couple married in 2015.
She too enjoyed the surprising realities of daily life.
"People queue for a bus! You'd get run over by Americans trying to pile onto a bus back home," she told ITV News.
Heather has delighted in the local lingo, documenting her favourite British-isms, including "jog on", "knickers in a twist", "keep your hair on".
Plus: "Everything's going pear-shaped. I mean, that's fabulous."
But besides the new parlance, do things still get lost in translation for the transatlantic couples?
For Jag, his attempts to deliver road directions have baffled Isha.
"I have found myself explaining directions - 'just go straight down this road' - and I get a call from Isha half an hour later saying, 'It's not a straight road'," he remembers.
Isha explains: "In my LA head, I'm thinking main road means about 10 lanes. And then I get to some of these roads and it's a single lane so I'm thinking I'm lost."
The hardest challenge for Heather's otherwise happy life with senior data analyst Simon is being away from home.
The 40-year-old university fundraising director, who speaks to her parents "every day", reckons she goes through "bouts of homesickness" on at least a quarterly basis.
"Mum sends me things from home all the time," she said.
Simon says the effect is instant as the "instant pang of nostalgia" kicks in.
"The first thing you do is smell the package because it smells like her mum and dad's home."
The other challenge for Heather is "living in a tupperware box".
That's not a complaint about the size of her London flat, but her description of the weather.
"It's very temperate all the time but it can be grey skies for weeks," she says.
Her solution is to book trips to sunny European destinations, an ease of travel that she said still surprises her friends back in the US.
Compared to minus-30 winters at home in Minnesota, Dana is not phased by the UK climate.
"I love the British weather," she says. But she agrees the hardest part of her life, in Enfield, north east London, is being absent from loved ones.
"London can be a lonely place... You blink your eye and it's 10 years and the family that you were surrounded with are almost like strangers."
So how did it go adapting to new family in a different country?
Though both have formed great relationships with their in laws, Heather and Simon have noticed stark differences in meeting the parents.
While Heather had to adapt to non-combative discussions at the dinner table, Simon faced more direct scrutiny after landing in the US.
"One of the first questions her dad asked me was ... how are your pensions doing?" he recounted, laughing.
Isha reckons it's best to roll out the red carpet for the mother-in-law.
"A little bit of royal treatment never hurts", she said. "I think all mother-in-laws like to be treated like a Queen."
She adds: "I think overall a little bit of tact, a lot of patience and a little bit of alcohol is the recipe for success."
Smooth family relations aside, when it comes down to it, are the couple's personal relationships really so special?
Or any different from any other partnership from two countries?
Jag reckons so.
He thinks he's absorbed an "element of the positive American spirit" and reckons his stiff British upper lip has "loosened" over the years.
Though his stand-out advice to Prince Harry may be familiar to many couples of shared nationality: to explain the basic rules of "key British sports" like cricket, rugby, "maybe even darts".
The reason? "To save some unnecessary explanations during the middle of the game."
Simon and Heather also believe the dynamic in their marriage is different to those who partner up with someone from their own land.
For Simon the relationship "works on more levels than usual", which makes it "deeper and more meaningful".
He explains: "You have a whole different culture and also you have to work on maintaining the family relationships as well."
"I would say you have to work harder at it because you're coming from different cultural backgrounds," she said.
"But what you get in return is just wonderful."
- Special coverage of Harry and Meghan – The Royal Wedding will be broadcast on ITV from 9.25am on Saturday 19th May.
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