Video report by ITV News Correspondent Sejal Karia
The world has reacted to the arrival of the first royal baby with an American nationality after Meghan, the Duchess of Sussex, gave birth to a baby boy.
Michelle Obama, Prime Minister Theresa May, Patrick J Adams and Ellen DeGeneres were among the well-wishers to send congratulations to the Duke and Duchess of Sussex after they welcomed their first child.
A beaming Prince Harry said both mother and baby are "doing incredibly well."
Meghan's mother, Doria Ragland, is said to be "overjoyed" at the arrival of her first grandchild, and is with her daughter and Prince Harry at Frogmore Cottage.
The baby boy weighed 7lb 3oz and was born at 5.26am, Buckingham Palace said.
Here is everything we know so far on the new royal baby:
Did Meghan and Harry know they were having a boy?
The baby's sex was a surprise for the delighted couple, who chose not to find out what they were having.
How and when was the birth announced?
Buckingham Palace confirmed Meghan had gone into labour during the early hours of the morning by @RoyalFamily on Twitter and said Harry was by his wife's side.
The palace confirmed the duchess had given birth to a baby boy through an official statement.
The news was also announced via the Duke and Duchess' Instagram account @SussexRoyal just before 2pm.
Meghan and Harry have chosen to celebrate privately as a family after the baby's arrival and will present their newborn to the public in a couple of day's time, Prince Harry said.
Where did Meghan give birth?
The Duke and Duchess kept this secret, and there is confusion as to where the birth took place.
It is thought that Meghan had wanted to opt for a home birth at Frogmore Cottage, but the Daily Mail reports that the Duchess was taken to a London hospital.
Frogmore Cottage was understood to be her preferred option over a midwife-led maternity unit at Frimley Park Hospital in Surrey or going private, such as the Kensington Ward of the Chelsea and Westminster Hospital in London.
Where does the baby fall in the line of succession?
The boy is seventh in line. The baby moves Harry’s uncle, the Duke of York, down into eighth place in the line of succession.
Princesses Beatrice and Eugenie will shift into ninth and 10th place, and the Earl of Wessex – the Queen’s youngest son – will drop out of the top 10 for the first time to 11th in line.
Remind me: How is the baby related to the rest of the royals?
The baby boy becomes the eighth great-grandchild of the Queen and the Duke of Edinburgh and the Prince of Wales’s fourth grandchild, the Duke and Duchess of Cambridge’s niece or nephew, and a cousin for Prince George, Princess Charlotte and Prince Louis.
Will he or she ever be monarch?
Unlikely. Future king George, plus Charlotte and Louis, are all further up the line of succession than Harry and Meghan’s baby, so it is a safe bet that the throne will stay on the Cambridge side of the family in years to come.
What will the baby be called?
Your guess is as good as ours.
Latest odds at the bookmakers have either Arthur, James, Philip, Edward and Albert among the predicted choices.
William and Kate chose royal favourites for their children.
But Harry and LA-born Meghan could break the royal mould and take inspiration from American traditions.
Or perhaps the former actress will follow the celebrity trend of picking an unusual first name for her offspring.
Will the baby be a prince?
Not at this stage. The baby boy will not be a prince, nor an HRH, because George V limited titles within the royal family in 1917.
So what will his title be?
The son can be known as the Earl of Dumbarton – because a first son of a duke is allowed to use one of his father’s other lesser titles as a courtesy title.
Harry was made Earl of Dumbarton by the Queen on the morning of his wedding, as well as being given a dukedom.
The boy will one day inherit the title the Duke of Sussex from Harry.
But the Queen could make the baby a prince?
Yes. The Queen stepped in ahead of George’s birth to issue a Letters Patent to ensure all the Cambridges’ children would have fitting titles, but that was done well ahead of time and this royal baby is much further down the line of succession.
Under George V’s rules, Harry and Meghan’s child and any future children would eventually become princes or princesses when Charles becomes king, because they would be the children of a son of a sovereign.
So even though the baby will be quite far down the line of succession, the Queen may decide to introduce the titles early so they do not have to be changed later on – unless Harry and Meghan prefer to adopt more low-key titles for their children.
Will Harry and Meghan hire a nanny?
There have been rumours that Meghan will turn to her mother, Doria Ragland, for help initially.
But it is likely they will hire a nanny eventually.
Harry has been close to all his nannies, especially Tiggy Legge-Bourke, and it is expected he and Meghan will arrange for a nanny to care for their baby while they are on official engagements.
Kate and William have the help of their full-time live-in nanny, Maria Teresa Turrion Borrallo.
Meghan’s close friend, Jessica Mulroney, had two nannies to help her with her twin boys and younger daughter.
There have been reports the duchess favours employing an American for the role and would consider a “manny” – a male nanny.
Where will the baby live?
Harry and Meghan have set up home in Frogmore Cottage on the Windsor Estate.
It was gifted to them by the Queen and has undergone renovations costing taxpayers an estimated £3 million.
Will the baby have dual citizenship?
Harry and Meghan could apply for their son to have dual US-UK citizenship.
Meghan is planning to become a British citizen – but at present is still a US citizen.
According to the American Embassy in the UK, a child born outside the US and in wedlock to a US citizen parent and a non-US citizen parent may acquire US citizenship at birth if the US parent lived in America for five years – two of which were after the age of 14.
Will they be moving to Africa?
Plans are being made for the couple to spend an extended period abroad, possibly in Africa, as a way of harnessing their international appeal and expanding on their Commonwealth work.
A decision is unlikely to be taken until 2020, when they have settled down with their baby.
The idea has raised concerns about the security cost to UK taxpayers.
But a Palace spokesman said the plans were speculative.
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