When and Markle first moved in together, they called Nottingham Cottage home. But despite being located in the grounds of Kensington Palace, the property wasn't exactly what the duchess would have expected from a residence.

In the couple's self-titled documentary series for , Meghan revealed that she was surprised at the size of her new home, labelling it "so small". The Sussexes revealed that when TV presenter came round for tea, she joked "no one would ever believe it" about the property.

"Kensington Palace sounds very regal, of course it does," Meghan said in the series. "It says 'palace' in the name! But Nottingham Cottage was so small."

And it turns out that the size of the grace-and-favour home the couple shared before their wedding became something of a catalyst in Harry's relationship with the rest of the , according to a new book.

Royal author Tom Quinn's new tome 'Yes Ma'am' makes a series of bombshell claims, including how Meghan found it that Harry's home was so small. According to royal sources the writer spoke to, this became a point of contention with his family, despite Harry not seeming to have an issue with it previously.

In the explosive new book, seen by the , a former staff member is quoted as saying: "Starting life as a member of the Royal Family in Nottingham Cottage was the beginning of all Meghan's troubles – she felt it was so small that it must be a reflection on how the Royal Family were belittling her husband. She just didn't understand that real royals don't care much about houses and material possessions because having always had them they take them for granted."

The royal author claims that the glaring differences between the Sussexes' smaller residence and and Princess Kate's home - a vast apartment with room for live-in servants in Kensington Palace - created "a vague feeling that the Kensington Palace staff tended to treat Harry as less important than his brother" in Meghan's eyes.

Another former staff member is said to have told the author: "Meghan spotted immediately that Harry wasn't quite as central to things as his brother William. This was the start of the whole grievance thing about being the spare. I don't think Harry had even thought much about the fact that he was a spare until well into his marriage.

"Meghan managed to give him more perspective because she could see the family from the outside and her experience of growing up was so totally different and, with her mixed-race heritage, as we now have to describe it, she was acutely sensitive to how people behaved towards each other; in fact, I think she was over-sensitive on Harry's behalf and convinced herself he was being treated as completely unimportant."

In Harry's memoir Spare, he wrote that he remembered feeling "embarrassed" of the home he could offer Meghan, when the couple moved into together for the first time, despite his excitement to share a home with her, and compared it to Kate and William's palatial apartment. "I was excited to welcome Meg to my home, but also embarrassed. Nott Cott was no palace," Harry wrote.

The Mirror has contacted Kensington Palace for comment.

Yes Ma’am: The Secret Life of Royal Servants by Tom Quinn, published by Biteback, will be published on February 27

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