Royal baby: What will the Duke and Duchess of Sussex name their first child?

The Duchess of Sussex is pregnant, Kensington Palace has announced.

The happy news came hours after the couple were seen arriving in Sydney for their first major international tour since their Windsor Castle wedding in May.

Following the news speculation is already mounting around the name of the next royal baby. 

The baby is expected to take the surname Sussex in the same way that Prince William's children, George, Charlotte and Louis have taken his title Cambridge as their last name at school and nursery.

Princesses Eugenie and Beatrice have previously used the surname York, after their father’s title Prince Andrew, the Duke of York.

But the Duke and Duchess of Sussex's baby will not be a prince or a princess unless the Queen steps in.

King George V - Harry's great great grandfather - limited titles within the royal family in 1917.

The couple may decide to go with a traditional name like Alice, Mary, Elizabeth or Victoria for a girl or Philip, Frederick, Charles, Arthur, Edward or James for a boy.

The pair are however forward-thinking royals and they may decide to surprise everyone when naming their first child.

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.

The Duchess may also seek inspiration from her friends.

Her confidante and stylist Jessica Mulroney has twin boys Brian and John, and a daughter Isabel Veronica, who is known as Ivy - who were pageboys and bridesmaid at the royal wedding.

Harry and Meghan's royal baby, who will be seventh in line, is extremely unlikely ever to be king or queen, meaning the couple have more freedom with their choices.

In comparison the Duke and Duchess of Cambridge chose to give their children traditional names, picking George for their firstborn, who is likely to one day be king.

One option - considered a favourite for a girl - is Diana in honour of Harry's mother.

William and Kate paid tribute to Diana, Princess of Wales in 2015 by choosing it as one of Charlotte's middle names.

The Duke was just 12 when the Princess Diana was killed in a car crash in Paris in 1997.

Meghan's mother, to whom she is close, is called Doria, and the ex-Suits star may want to pay tribute to her as well.