Prince Harry's "very important first duty" as soon as Meghan gives birth to royal baby

It's not long until Prince Harry and Meghan Markle's baby arrives with speculation rife as to how many traditions they will adhere to with their birth plan.

There's been mention of a "holistic birth" and a more natural method as well as rumours Meghan will snub the Lindo Wing where the Duchess of Cambridge gave birth to her three children.

Amongst all the rumours, one thing seems pretty certain, Prince Harry won't be pacing the corridor outside.

In the new ITV documentary, Secrets of the Royal Babies: Harry and Meghan, royal historian Kate Williams says Prince Harry is "so likely" to attend the birth.

"He'll be there doing yoga moves with Meghan," she jokes.

"What normally happens is that there is an encrypted phone that cannot be tapped and he will tell her [whether it's] a girl or boy," explains Williams.

Queen Elizabeth II has to know before Prince Charles or Meghan's mother because she's the "head of the family".

Prince William also followed the same rule when his children were both. After Prince George was born he called the Queen on an encrypted phone line to let her know George had arrived, then rang Kate's family.

The rule is just one of the traditions that the couple has to adhere to thanks to royal protocol.

After the phone call is made the Duke and Duchess get a few moments with the little one before an official statement is issued by the palace then the selection of godparents, then the Christening...

But when will we know the name?

Historically, it could take quite awhile. Prince Charles was nameless for about a month, but in the case of George and Charlotte their names were announced just two days after they were born, whereas Prince Louis' name was shared four days later.

Hopefully we won't have to wait too long.

At least their new home at Frogmore Cottage is nearly ready and they are already looking at childcare and birth plans.