: “The Duke and Duchess sought medical advice about the risk of the Zika virus on the islands of Fiji and Tonga and there will be no change to the planned schedule.”
They will be bringing Meghan's best friend Jessica Mulroney and her husband Ben who are "flying from Toronto to Sydney" to support the couple in an “unofficial” capacity.
Canadian stylist Jessica , 38, is married to TV presenter husband Ben, 42, the son of former Canadian prime minister Brian Mulroney.
Harry and Meghan share a tender moment as they hold hands during the appearance in Sydney Credit: Reuters Meghan looked thrilled as the couple visited in Sydney, Australia Credit: Splash News The announcement five months after their big day has sparked speculation that the royal tot was conceived on their mini-moon to Dublin - or even at a pal's wedding.
It's thought the seventh in line to the throne could be traced back to Harry's best friend Charlie Van Straubenzee's nuptials on August 4, when the couple were spotted looking loved up and celebrating her 37th birthday.
The couple have already been given the first gift for their unborn baby Credit: Splash News The Royal couple during their trip to Ireland, their first trip abroad as a married couple Credit: Splash News Others have speculated that the tot could have been conceived during their royal tour to Dublin in July, their first trip together as a married couple .
The Duchess of Sussex was seen enjoying a glass of champagne during the , suggesting she was not pregnant or didn't know she was at that point.
Prince Harry was even asked on the trip if he and Meghan were trying for a baby when one woman said: "My husband also has red hair and he gave me five children - when are you and Meghan going to get going?' - to which he replied: "Five children? Too many".
Prince Harry stresses importance of families in first interview aired since news Meghan Markle is pregnant Meghan, who found fame playing Rachel Zane in the US drama Suits , has had a 12-week scan, meaning her baby could be due in late April, possibly around St George's Day on April 23.
The good news came just hours after Meghan and Prince Harry, 34, touched down in Australia for the first leg of their 16-day royal tour Down Under.
The Duke and Duchess of Sussex shared the happy news with the "delighted" Queen and other members of the Royal Family before their departure, at Princess Eugenie's wedding on Friday.
Seemingly less thrilled was mother of the royal bride Fergie , who sent a flurry of tweets immediately after the announcement - none of them about the baby.
What we know so far: Kensington Palace announced the news this morning Credit: Kensington Palace Meghan wore a large blue coat for the wedding of Princess Eugenie, fuelling speculation she was pregnant Credit: PA:Press Association Concern that Fergie felt Eugenie had been upstaged by the announcement appeared to be confirmed by her total lack of reaction to the Duke and Duchesses' big news - though she was celebrating her own birthday.
Elsewhere speculation about the pregnancy had reached fever pitch earlier after Meghan was seen clutching a number of purple folders to her stomach in Sydney in an apparent bid to disguise her baby bump.
Kensington Palace swiftly confirmed these rumours on Twitter this morning, writing: "Their Royal Highnesses The Duke and Duchess of Sussex are very pleased to announce that The Duchess of Sussex is expecting a baby in the Spring of 2019."
They added: "Their Royal Highnesses have appreciated all of the support they have received from people around the world since their wedding in May and are delighted to be able to share this happy news with the public."
Meghan and Harry were seen enjoying a private moment hours before their big announcement Credit: Nine The besotted pair tied the knot in May Credit: PA:Press Association The couple announced their engagement in September last year Credit: EPA Meghan appeared in excellent health in the early stages of her pregnancy Their news came nearly five months to the day that they were married in a lavish ceremony at St George's Chapel in Windsor.
Just last week rumours circulated that Meghan was pregnant after she appeared at Princess Eugenie's wedding wearing a long, loose-fitting coat.
This morning the pair held hands and smiled as they arrived in Australia , accompanied by a ten-man entourage for their first international tour as a couple.
The mum-to-be was wreathed in smiles as she and Harry were greeted by excited fans as they stepped off the plane.
A LOVE STORY: How the whirlwind romance of Prince Harry and Meghan Markle unfolded
July 2016: Meghan Markle and Prince Harry met through friends, becoming an item
November 2016: Prince Harry confirms the couple's relationship, condeming the "abuse" of his girlfriend
May 7 2017: The couple were snapped kissing in public for the first time
September 2017: Meghan Markle gave an insight into the couple's relationship, saying they were "two people who are really happy and in love"
November 27 2017: The couple's engagement was announced, with it revealed Prince Harry proposed over a roast chicken dinner
March 23 2018: On a trip to Belfast, Meghan jokes when shown baby products "I'm sure at some point we'll need the whole (lot)".
May 17: Drama around the wedding unfolds, with Meghan's father revealed to have been involved in staging paparazzi photos
May 19: The couple are married at St George's chapel, Windsor Castle and become the Duke and Duchess of Sussex
June 14: Meghan undertakes her first joint engagement with the Queen on a day trip to Cheshire, and body language experts say the pair got on famously
October 12: Harry and Meghan return to St George's Chapel for Princess Eugenie's wedding to Jack Brooksbank just five months after they pledged their love for one another in the same Windsor Castle venue.
October 15: The duke and duchess touch down in Australia ahead of their first royal tour as a married couple
October 15: The duke and duchess are "very pleased" that Meghan is expecting a baby in the spring of 2019, Kensington Palace announces.
And they were seen enjoying a tender moment together as they strolled through the gardens of Admiralty House, moments before the announcement.
The latest royal could even end up sharing a birthday with their great-grandmother, the Queen, who celebrates hers on April 21.
And if she's overdue, the newborn could share a birthday with their cousin, Princess Charlotte , who was born on May 2.
Harry and Meghan's baby will be a first cousin of Prince George, Princess Charlotte and Prince Louis - but will not be a prince or princess themselves unless the Queen steps in ahead of the birth.
Doria Ragland with her daughter on her wedding day Credit: Getty - Contributor Doria could come over to the UK to help Meghan look after the newborn Credit: AP:Associated Press Harry and Meghan tied the knot in a fairytale wedding in May Credit: PA Meghan's mum Doria Ragland, 62, is expected to fly over for the birth and has been mooted as the nanny for the infant after she seen taking baby-care classes in Pasadena, California, earlier this year.
In a statement issued through Kensington Palace, Ms Ragland said she was "very happy at this lovely news and is looking forward to welcoming her first grandchild".
But the Palace refused to say whether Meghan's dad Thomas, 74, had been told about the baby news.
Despite their ongoing rift, Thomas told ITV's Good Morning Britain a month after his daughter's wedding: "She's wanted children for a long time and when she met Harry and she spoke about how much she loves him, there's got to be a child in the making, somewhere soon."
The new arrival will be the seventh in line to the throne Thomas saw daughter Meghan graduate but had to miss her wedding to Prince Harry for health reasons Credit: James Breeden - The Sun Thomas was unable to attend Meghan's big day citing ill health and has since made a series of ill-advised blunders, apparently courting publicity generated by his royal daughter.
Meghan's vocal half-sister Samantha has so far avoided commenting on the pregnancy, despite frequent attacks on her sibling in the past.
Prince Harry has previously been open about wanting to have kids, but managed to avoid the question after the pair were married.
He was even directly asked about the couple's plans to start a family while on a two-day visit to Ireland.
Meghan's half-sister Samantha has frequently criticised the Duchess Credit: supplied by Pixel8000 The new royal baby will likely take the surname Sussex - similar to how Prince William's children, George, Charlotte and Louis have all taken Cambridge as their last name.
Princesses Eugenie and Beatrice have also previously used York as their surname - in recognition to their dad Prince Andrew's title as the Duke of York.
Meghan Markle's best friend and stylist Jessica Mulroney is said to be joining the Duke and Duchess on their royal tour to Australia Jessica, 38, and her TV presenter husband Ben, 42, are said to be flying from Toronto to Sydney Credit: Getty - Contributor
Aerial video of pregnant Meghan Markle and Prince Harry walking and holding hands at Admiralty House in Sydney, Australia The couple land in Sydney Australia for the start of their royal tour//twitter.com/theresa_may/status/1051755594456227840
Harry and Meghan became engaged following a whirlwind 16-month romance after going on a blind date in London.
The prince has told how "all the stars were aligned" when they met and spoke of his hopes for a future family.
"This beautiful woman just sort of literally tripped and fell into my life, I fell into her life," he said when their engagement was announced last November.
"Hopefully we'll start a family in the near future."
Today's announcement made waves on social media, with PM Theresa May writing on Twitter: "My warmest congratulations to the Duke and Duchess of Sussex on the happy news they are expecting a baby in the spring. Wishing them all the best."
Grant Harrold, a former butler to Charles, William and Harry, tweeted: "Congratulations to The Duke and Duchess of Sussex who are expecting their first child in the spring."
European Commission spokesman Margaritis Schinas told a press conference in Brussels: "On behalf of the President of the Commission (Jean-Claude Juncker), the College of Commissioners and all of us, we would like to wish wholeheartedly all the very best to the royal couple on this great news."
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