"An ordinary woman is not going to get to become a princess," a palace insider tells PEOPLE

Kate Middleton and Meghan Markle are more than just self-assured partners for Prince William and Prince Harry – they’re modern women who are changing the monarchy.

Since Meghan officially joined the royal family with her May wedding to Harry, there has been a shake up in its synergy. But many believe the shift was bound to happen.

“Wives do change the dynamic, and they both have very strong wives,” a palace insider tells PEOPLE in this week’s cover story. “If you bring two independent-minded women from the real world into the royal world, they are going to want to have an impact.”

And if that means ruffling some feathers among the palace establishment? “Some feathers need to be ruffled.”

Wimbledon Tennis Championships, Day 12, The All England Lawn Tennis and Croquet Club, London, UK - 14 Jul 2018
Credit: James Gourley/BPI/Shutterstock

Rumors of tension between Meghan and Kate have recently dominated headlines, flared up by confirmation that Meghan and Harry will move out of Kensington Palace, where Kate and William live with their three children, next year. Both are focusing on their growing families: Meghan and Harry are expecting their first child this spring, while Kate and William welcomed Prince Louis in April.

“[The move] will be the best thing for all of them,” says a family friend. “Like Meghan and Kate, Harry and William have totally different roles. But the brothers will always come together because they are Diana’s sons.”

Prince William, Prince Harry, Meghan Markle and Kate Middleton
| Credit: Paul Grover- WPA Pool/Getty

The Duchess of Sussex is still struggling to find her footing as a member of the royal family, several sources tell PEOPLE.

“The most difficult job in the royal family is to work with Meghan’s ambitions and make them realizable,” says another insider.

Meanwhile, Kate has established her place as a future queen and doting mother.

“They are very different characters,” says the family friend.

Trooping the Colour 2018
Kate Middleton and Meghan Markle in June
| Credit: James Whatling/MEGA

However, both Meghan, 37, and Kate, 36, are exceedingly capable of owning the spotlight.

“An ordinary woman is not going to get to become a princess,” says the palace insider. “There is a necessary strength of character and ambition and single-mindedness. It takes someone really strong. That is Kate and Meghan.”