A new memoir asserted that Meghan Markle yelled at Kate Middleton's staff and drama ensued between the royal wives when the Duchess of Sussex had to recognize that she was not married to the next King in line.

Numerous incidents throughout the former "Suits" actress' first few months of being a working member of the British royal family reportedly prompted the Duke and Duchess of Sussex to relocate from Kensington Palace to Frogmore Cottage in Windsor.

A new book released by Tom Quinn entitled "Kensington Palace: An Intimate Memoir From Queen Mary to Meghan Markle" aims to lift the curtain on the mystery of the royals' lives behind closed doors.

Quinn interviewed Kensington Palace's former staffers -- including a number who worked at the royal residence wherein the Sussexes were living there together prior to their royal wedding.

According to an excerpt from the biography, sources detailed the differences which served as factors to Markle clashing with her sister-in-law Middleton.

"Kate is actually one of the nicest royals, and she hasn't let life in her extremely grand apartment at Kensington go to her head, or at least not too much," a palace insider said.

Middleton was reportedly nice to the staff and was very warm to Markle when she first arrived. The insider noted that Markle was jealous of her.

Sources in the memoir alleged that Markle struggled with having a lower rank in the monarchy than Prince William and Middleton. The source asserted that she had found that difficult to tackle. "And although Harry loved their cottage in the grounds, Meghan was conscious that it was tiny in comparison to the vast apartment complex where Kate and William live."

Also Read: Meghan Markle Diva Behavior: Prince Harry's Wife Has Difficult, Demanding Attitude?

A second insider divulged regarding the incident that led to the division of the so-called "Fab Four."

The source opened up to the author how Markle's yelling at a staff member was not tolerated by the Duchess of Cambridge.

Kensington Palace's servants have many stories left to tell, including the reasons behind Prince Harry's wife falling out with his brother Prince William's wife.

The yelling incident marked the beginning of discussions on leaving Kensington Palace.

The source narrated, "Like many people not used to dealing with servants, Meghan overdoes the imperiousness; so, on the one hand, she wants to be like Diana, a people's princess, and on the other she wants people to stand to attention when she clicks her fingers."

Markle apparently behaved this way because of the kind of treatment she received when she married into the royal family as a divorced, mixed-race American. People's judgment of her led her to overreact and she does not possess Middleton's calm and pleasant way of handling people.

Due to the Duchess of Sussex's attitude towards her staff, they wittily made up unflattering nicknames for her including "Me Gain," "Duchess of Difficult," Di 2" or "Di Lite."

According to royal expert Ashley Pearson, Markle commenced her day at the palace at 5:30 AM. She would then message her staff with a barrage of instructions that overwhelmed them.

The full book is set to be released on May 14.

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