The Princess Diaries is coming to life for Meghan Markle!

The Princess Diaries is coming to life for Meghan Markle!

As she begins life as the new Duchess of Sussex, Meghan will have a highly-regarded new aide at her side. Samantha Cohen, 49, is set to become Prince Harry’s private secretary when the current head of the couple’s household leaves this summer.

But Cohen, who until April was Queen Elizabeth‘s assistant private secretary, has already been advising Meghan, 36, behind the scenes. Cohen has been helping the new duchess with protocol and navigating how to address people and manage her new position in the royal world, an insider tells PEOPLE.

Although Meghan comes across as someone on top of her new surroundings, the intricacies of royal life would be baffling at best and sometimes restrictive to a woman who has made her way in the outside world, including in the tough world of Hollywood.

The Prince of Wales' 70th Birthday Patronage Celebration, Buckingham Palace, London, UK - 22 May 2018
Credit: Tim Rooke/REX/Shutterstock

Cohen is believed to have tendered her resignation as assistant private secretary to the Queen, 92, after the monarch’s top staffer, Lord Geidt, left late last year. But she was persuaded to stay on and see through the organization of the Commonwealth Heads of Government Meeting of April.

Soon after, it emerged that Ed Lane Fox was leaving Harry’s household after about five years – and Cohen was chosen as his successor as an “interim” private secretary.

Prince Harry Marries Ms. Meghan Markle - Windsor Castle.
Samantha Cohen attends Prince Harry and Meghan Markle’s wedding
| Credit: Pool/Max Mumby/Getty

Meghan previously said she wants to “hit the ground running” with her royal duties and she has surprised royal watchers with the number of outings and engagements – both in public and in private – she and Harry have done in the months leading up to the royal wedding.

The Queen Visits Newmarket
Queen Elizabeth accompanied by Samantha Cohen
| Credit: Max Mumby/Indigo/Getty

While Meghan also has new palace aide Amy Pickerill helping run her office and her official duties, Cohen has been a strategic and wise voice in the background. “She is a brilliant choice and has been helping Meghan adjust to the new surroundings,” says an insider. Some believe that she might stay longer than the “interim,” as outlined by Kensington Palace when they made the announcement of Lane Fox’s departure on April 27.

Prince Harry And Meghan Markle Visit Edinburgh
Amy Pickerill
| Credit: Mark Cuthbert/UK Press/Getty

She will be in place by the time the couple heads to Australia, and likely some surrounding countries in the region like New Zealand, Fiji and Tonga, around the time of the Invictus Games in Sydney in October.

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It is interesting that Cohen – who was the Queen’s press secretary before rising to the private secretaries’ office — is Australian and the Commonwealth is an area that the Queen clearly sees Harry and his wife taking a lead in. Harry was made Commonwealth Youth Ambassador as CHOGM kicked off, and Meghan joined him at two events that week – including one on female empowerment.

Prince Harry and Meghan Markle kiss as they exit St George's Cha
Prince Harry and Meghan Markle
| Credit: Sipa via AP Images

The Commonwealth is an important area of the Queen’s life and the legacy (and she would have been delighted that each of the 53 countries were represented on Meghan’s wedding veil.) The Queen’s recent participation in the ground-breaking conversation with veteran broadcaster Sir David Attenborough promoted her Commonwealth Canopy of protected forests around the world. The unveiling of that documentary, which was watched by media and friends at Buckingham Palace, was helmed by Cohen.