The Duke and Duchess of Sussex have revealed that their one-year-old son, Archie, will have a younger sister.

The pair posted a black-and-white photo of themselves under a tree, with Harry putting his hand on Meghan’s head while she cradles her baby belly.

“We can confirm that Archie will be a big brother,” a representative for Prince Harry and Meghan stated. “The Duke and Duchess of Sussex are overjoyed to be expecting their second child.”

Misan Harriman, a Nigerian-born British photographer who has known the couple for years and snapped the portrait that accompanied their pregnancy announcement, tweeted: “Meg, I was there at your wedding to witness this love story begin, and my friend, I am honoured to capture it grow.”

“To be asked to help share this absolute joy after such an unimaginable loss and heartache is a marker of true friendship,” Mr Harriman told British Vogue after the latest news.

“Meg reminded me that had I not introduced her to a mutual friend then she wouldn’t have met Harry.

“I’m grateful for whatever small part I played.”

“Congratulations to The Duke and Duchess of Sussex on this joyous news!”

“With the tree of life behind them and the garden representing fertility, life and moving forward, they didn’t need any direction, because they are, and always have been, waltzing through life together as absolute soulmates.” he stated of how he captured the photograph.

Buckingham Palace responded to the news by saying, “Her Majesty, Duke of Edinburgh, Prince of Wales and the entire family are delighted and wish them well.”

The pair is said to have picked Valentine’s Day to disclose the news “because they were happy and liked the idea” that it was a day to celebrate love.

The date is also reminiscent of Diana, Princess of Wales, who declared she was expecting her second child, Prince Harry, on February 13, 1984, news that was widely publicized on Valentine’s Day.

The announcement for Valentine’s Day comes only five days after the royal family celebrated the birth of Princess Eugenie’s first child, a baby boy.

The baby will be the Queen and the Duke of Edinburgh’s 11th great-grandchild.

The new baby will be entitled to be a Lady, but will be known as Miss (first name) Mountbatten-Windsor instead, in accordance with Harry and Meghan’s desires.

When the Prince of Wales ascends to the throne, the infant, like Archie, will be entitled to be an HRH and a princess.

To marry, the new infant will not need the monarch’s approval.