The newlyweds, who married in Windsor last May, are just weeks away from welcoming their first child.
As the nation waits for the Queen and Duke of Edinburgh's eighth grandchild to arrive, please enjoy everything we know about royal baby Sussex so far.
When is the Royal baby due?
Though Kensington Palace have only publicly declared that the royal baby is due in the spring, six-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.
This means he or she could easily be born on the same day as their great-grandmother (yes, the Queen), who will celebrate turning 93 on April 21.
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.
Where will the Duchess of Sussex give birth?
No one outside of the family knows for sure but staff at the Lindo Wing at St Mary’s Hospital in Paddington, London, have been advised not to take holiday in the spring, sparking speculation the Duchess plans to give birth there.
Contrary to earlier reports saying the former American actress plans to give birth on the NHS, she may follow in the footsteps of the Duchess of Cambridge instead. Kate had her three children at the same private maternity unit and Princess Diana gave birth to Harry there in 1984.
A source told the Telegraph: “Staff at the Lindo Wing have been asked not to take holiday in April. Everyone thinks it’s got something to do with the royal baby but no one is confirming anything.”
It had been reported that Meghan, 37, planned to give birth on the NHS at Frimley Park Hospital in Surrey. It is seven miles closer than the Lindo Wing to Frogmore Cottage in Windsor, where the Sussexes are due to move to this year.
Giving birth in the Lindo Wing
The £6,000-a-night Lindo wing offers a “five-star” birthing experience with expectant mothers accommodated in spacious private rooms with en-suite bathrooms.
Patients are invited to pick their meals from lavish a la carte menus - including a wine and champagne list - and are even offered a celebratory post-labour afternoon tea.
The first night in Lindo wing costs £5,900 (for the 'normal' delivery package) and every additional night is charged at £1,175.
Patients can also pay extra for a deluxe package, where the rooms are slightly bigger, which costs £6,275 for the first 24 hours and £1,550 for extra nights.
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 of Sussex are due to move into Frogmore Cottage in the grounds of Windsor Castle this year. The propertym however, is still under-going extensive refurbishment.
Since 2017 the couple have been living at Nottingham Cottage, in the grounds of Kensington Palace, near the Duke of Cambridge and his family. The move means they will be 20 miles away from them.
Read more about Nottingham Cottage here.
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.
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 baby shower?
Late February, Meghan embarked on a "private" five-day trip to New York without any royal aides. Though we now know the Duchess managed to enjoy many activities incognito (like having macarons at Ladurée in Soho and shopping at children's boutique Bonpoint), sources told US media her solo stint would end with a baby shower just in time to call the paparazzi.
The unexpectedly public event happened seemed to happens as quickly as media pens could be set up outside The Mark Hotel on New York's Upper East Side.
Many deliveries - including a flat pack baby coat and buckets of flowers, including pink roses, while a flat pack baby cot - were dropped off throughout the morning before guests arrived.
Abigail Spencer, the actress who played 'Scottie' alongside the Duchess in legal drama Suits, was one of the first to be photographed walking through the front door, immediately recognisable despite a beanie hat and dark glasses.
Other celebrity guests arrivals include Amal Clooney, CBS news anchor Gayle King, stylist Jessica Mulroney, and Misha Nonoo (the fashion designer who reportedly set Harry and Meghan up on a blind date).
Reportedly, the baby shower - which cost over £100,000 - itself was partially funded by tennis ace Serena Williams, who paid to host in it 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.
She was once again celebrating with Serena Williams and Jessica Mulroney before the women head their separate ways around 10.15pm - the Duchess returning to The Mark hotel.
The Duchess is reported to be awaiting a second baby shower - thrown by her British friends - in the next few weeks.
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