The newlyweds, who married in Windsor last May, are days away from welcoming their first child, who will be seventh in line to the throne.
As the nation waits for the Queen and Duke of Edinburgh's eighth great-grandchild to arrive, here is everything we know about royal baby Sussex so far, including what we know about how the Duchess plans to give birth.
When is the Royal baby due date?
Though Kensington Palace have only publicly declared that the royal baby is due in the spring, nine-month pregnant Meghan let slip that she is due at the end of April or early May during an engagement in Birkenhead earlier this year.
The couple announced their pregnancy to family and friends at Princess Eugenie’s wedding in October, just days before their royal tour of Australia, New Zealand, Fiji and Tonga.
The recent launch of Harry and Meghan's Instagram account, @sussexroyal, has led many to believe the royal baby will come very shortly.
Royal baby gender - girl or boy?
If the couple do know the gender, they're keeping it very quiet. They recently said they'd be “thrilled” with a baby boy or girl. There were rumours the Duchess was planning to bring up their child gender neutral, although those rumours have been denied.
The current odds, courtesy of William Hill, are:
- Girl - 4/7
- Boy - 5/4
Where will Meghan give birth?
The Duke and Duchess of Sussex are to keep plans for the birth of their baby private, they have confirmed, as they decide they will not undertake a Lindo Wing-style appearance to show their new arrival to the watching world.
The Duke and Duchess said they would be "celebrating privately as a new family" after the birth as a first priority.
While photographs of the baby will be taken in the following days, the family of three will not greet members of the public in the same way as the Cambridges and other members of the Royal Family have done.
Instead, they are likely to follow in the footsteps of the Queen with hopes for a home birth, expected to be at their new home in Windsor.
The palace are expected to issue a short written announcement confirming the Duchess is in labour, with a second to follow upon the safe arrival of the baby, giving details of its sex, weight and time of birth.
It is understood that photographs of the baby, taken in Windsor, will be issued later, when he or she is a few days old.
The couple are also likely to utilise their Sussex Royal Instagram page to share news and images of their choice.
Earlier this year, reports suggested Meghan may opt for an NHS hospital in Surrey, Frimley Park, just 15 miles from their new home Frogmore Cottage on the Windsor estate.
Meghan's birth plans differ starkly from the Duchess of Cambridge who gave birth to all three of her children at the Lindo private maternity unit at St Mary's Hospital in Paddington, London. Princess Diana gave birth to Harry there in 1984.
What sort of birth is Meghan planning?
The Duchess has reportedly appointed her own delivery team to oversee the birth - which could well be a home delivery.
If she does deliver Baby Sussex at Frogmore Cottage, she would be following in the footsteps of the Queen, whose four children were born at either Buckingham Palace or Clarence House.
An "unnamed female doctor" will apparently lead the team instead of Royal Household gynaecologists Alan Farthing and Guy Thorpe-Beeston, the Mail on Sunday reported.
Meghan has broken from royal tradition by not appointing the Royal Household gynaecologists because she does not want "the men in suits" to supervise the birth.
"Meghan said she doesn’t want the men in suits. She was adamant that she wanted her own people. It did leave a few of us a little baffled," a source was quoted as saying.
Frimley Park vs the Lindo Wing
If reports of a home birth are incorrect, Meghan may end up giving birth at NHS-managed Frimley Park Hospital in Surrey, which does not offer private care to any patient in their 938 beds. It was, however, one of only three hospitals rated 'outstanding' by the Care Quality Commission in 2015.
There are 14 labour rooms in the general ward and they handle thousands of births each year, including the births of Earl Edward and Countess Sophie of Wessex's two children as well as Chris Evans and wife Natasha Shishmanian's twins in 2018.
While most women who give birth at Frimley Park leave within 12 hours, private postnatal rooms are available for £100 a night. For a little bit of 'Lindo', Meghan could also stay in one of the hospital's four birthing rooms (in The Mulberry Birth Centre), which boast a “homely environment” for “birth without medical intervention”.
It's in stark comparison to the £6,000-a-night Lindo Wing, favourited by the Duke and Duchess of Cambridge, which offers a “five-star” birthing experience with expectant mothers accommodated in spacious private rooms with en-suite bathrooms.
The first night in Lindo wing costs £5,900 (for the 'normal' delivery package) and every additional night is charged at £1,175. Read more about the Lindo Wing here.
What will the royal baby be called?
There is much suspense as to what the Duke and Duchess of Sussex will call their baby.
The youngster will be born into the British royal family, where tradition is an intrinsic part of the Windsors' lives. If they go classic, possibilities include Alice, Mary, Elizabeth or Victoria for a girl, and Philip, Frederick, Charles, Arthur, Edward or James for a boy. Of course, the pair are also forward-thinking royals and the Duchess has her own American upbringing to draw on.
Canadian-born Autumn Phillips, and husband Peter Phillips, opted for a non-traditional name for their daughter Savannah - the Queen's first great-grandchild - in 2010.
In the US, the most popular name for a baby girl is Emma and Liam for a baby boy. In the UK, the most popular name for a girl born in 2017 was Olivia and, for a boy, Oliver. In short, it's anyone's guess.
Where will the baby fall in the line of succession?
Seventh in line, which means it's highly unlikely the child will ever be monarch.
The baby will have three cousins: Prince George (a future king), Princess Charlotte and Prince Louis - all of whom are further up the line of succession. It is a safe bet that the throne will stay on the Cambridge side of the family.
The baby will bump Harry's uncle, the Duke of York, into eighth place in the line of succession.
His daughters - Princesses Beatrice and Eugenie - will move into ninth and 10th place. Prince Edward, Earl of Wessex - the Queen's youngest son, drops out of the top 10 for the first time to 11th in line.
What title will the new royal baby have?
The Duke and Duchess of Sussex's baby will not be a prince nor a princess unless the Queen steps in.
King George V - Harry's great great grandfather - limited titles within the royal family in 1917. This means the couple's first born, as a great-grandchild of the sovereign, is too far down the line of succession to be an HRH.
George V declared that: "the grandchildren of the sons of any such Sovereign in the direct male line (save only the eldest living son of the eldest son of the Prince of Wales) shall have and enjoy in all occasions the style and title enjoyed by the children of Dukes of these Our Realms."
The eldest son and heir apparent of a duke can use one of his father's lesser grade peerage titles by courtesy, according to Debrett's.
With this in mind, a first son of Harry's would become Earl of Dumbarton - one of the subsidiary titles Harry received from the Queen on the morning of his wedding. A daughter would be Lady (first name) Mountbatten-Windsor, and any subsequent sons Lord (first name) Mounbatten-Windsor.
Will the baby have dual citizenship?
The Duke and Duchess could apply for their child to have dual US-UK citizenship.
The Duchess is in the process of becoming a British citizen but it is not known whether she will hold dual nationality, and at present is still a US citizen.
According to the American Embassy in the UK, a child born outside of 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.
Where will the family live?
The Duke and Duchess have now moved out of Kensington Palace and into their new home Frogmore Cottage.
The couple are settling into their new life away from London on the Windsor Estate, having carried out extensive £3 million renovations to the house. The Sussexes have lived at Nottingham Cottage at Kensington Palace since their engagement and following their wedding.
Work on the listed property in Berkshire - including changing it from staff apartments into one mansion - overran and it was reported that the couple made constant design changes, meaning the builders fell behind schedule. The duke and duchess, who will foot the bill for furnishings, are said to have hired former Soho House interior designer Vicky Charles to transform their new pad.
With this in mind, there have also been speculative reports that the royal couple are considering a major move to Africa which would enact an entirely unexpected upbringing for baby Sussex.
Will the Sussex's hire a nanny?
Most likely. Harry has been close to all his nannies and it is likely 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.
The couple will almost certainly call upon the help of Meghan's mother Doria Ragland who will no doubt make frequent visits to London from her Los Angeles home to visit her grandchild.
Ms Ragland has reportedly already arrived in the UK for the birth of baby Sussex, apparently hiring a house and dog sitter to take care of American affairs while she supports the new parents at Frogmore Cottage.
Read more about what it's really like to be a royal nanny here.
Who will be godparents?
Loyal friends of the Duke and Duchess of Sussex look set to be asked to be godparents to the couple's first baby.
Harry and Meghan are predicted to turn to their confidantes, many of whom had VIP seats in the Quire of St George's Chapel at the royal wedding last May, and whose children were their pageboys or bridesmaids.
Royal infants usually have more than the standard three godparents. Prince Louis has six, future king Prince George has seven and Princess Charlotte has five. So who might be asked to be Baby Sussex's godparents?
Meghan's stylist and best friend, Jessica Mulroney is expected to play an important part in the baby's life. She supported Meghan in the difficult days leading up to the wedding amid the turmoil caused by the absence of her father, Thomas Markle.
The duchess's close friend, Benita Litt runs her own brand agency and helps others to start businesses. Meghan has spent Christmas with the Litt family in the past. She is godmother to Mrs Litt's daughters, Rylan and Remi, and also chose them to be her bridesmaids.
Tennis champion Serena Williams is said to have hosted Meghan's lavish baby shower in the £57,400-a-night penthouse of the Mark Hotel in New York City. The pair have been friends since 2010.
And who from Harry's side?
The van Cutsems have been long-standing family pals of Harry, William and the Prince of Wales for many years. Harry might pick Major Nicholas van Cutsem, whose daughter Florence was a bridesmaid at the royal wedding and is Harry's goddaughter.
Tom "Skippy" Inskip has long been considered Harry's wingman and was at his side during his partying days and Guy Pelly, dubbed the royal court jester for his wild ways could also be considered. Guy, whose family are wealthy Kent landowners, has settled down in recent years, marrying American hotel heiress Elizabeth "Lizzy" Wilson.
Who will the royal baby grow up with?
Baby Sussex will have an important bond with his or her cousins, growing up together with the shared experience of the upsides and downsides of being part of one of the world's most famous families.
The child will be a first cousin of Prince George, Princess Charlotte and Prince Louis. The youngster will also have a host of second cousins - all great-grandchildren of the Queen.
Days will be spent at the polo with Peter and Autumn Phillips' fun-loving children Savannah and Isla, and Zara and Mike Tindall's cheeky daughter Mia and her younger sister Lena.
What happened at Meghan's New York baby shower?
In February, Meghan embarked on a "private" five-day trip to New York without any royal aides which ended with a luxurious baby shower at The Mark Hotel on New York's Upper East Side.
Abigail Spencer, the actress who played 'Scottie' alongside the Duchess in legal drama Suits, was one of the first guests to be photographed walking through the front door. Other celebrity guests included Amal Clooney, CBS news anchor Gayle King, stylist Jessica Mulroney, and Misha Nonoo.
The baby shower - which reportedly cost over £100,000 - was partially funded by tennis ace Serena Williams, who paid to host it in The Mark's penthouse suite. Other reported extravagances include a performance by Kanye West’s favourite harpist, a candy floss machine and £150 steaks.
The Duchess rounded off her New York trip with a three and a half hour night out with her best friends, leaving her hotel just before 7pm and heading to the trendy Ralph Lauren Polo Bar.
What about charitable donations?
Harry and Meghan have asked the public to donate to four children's charities, instead of sending royal baby gifts. The suggested charities are the Lunchbox Fund, Well Child, Baby2Baby and Little Village.
The royal couple have thanked royal fans for "making a real difference" by donating. A post on their @SussexRoyal Instagram account said: "On behalf of The Duke and Duchess (and Baby Sussex), we thank you so much."
The message added: "Their royal highnesses wanted you to know the impact of your support - the direct effect your donation, energy, and action made!
"YOU chose to be part of the collective good, and you have a made a real difference."
Did they have a babymoon?
The royal parents-to-be reportedly spent three nights at Heckfield Place, the transformed five-star Georgian manor house in Hampshire, ahead of the arrival of their first child.
The couple apparently stayed in the Long Room at the luxury hotel, where chef Skye Gyngell runs the kitchen using ingredients from the ground.
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