Princess Diana shared a special bond with her two sons, Prince William and Prince Harry. And if anything, she wanted to make sure that she would be the closest woman in their lives, especially when they were kids.

As such, the Princess of Wales felt threatened by some of her sons’ nannies after realizing that they have gotten too close to her boys. At one point, she decided to sack some of them to cut their growing bond with the Duke of Cambridge and the Duke of Sussex.

During an interview on Yahoo’s “The Royal Box,” royal historian Louise Heren said that not all nannies could be trusted. This is why members of the royal family are very particular with the nannies that they hire.

“Some nannies do spill the beans,” she said. “Nannies are sometimes sacked for inappropriate behavior, getting too close to the children. A couple of the nannies that Princes William and Harry had the rumor is that they got too close. That close bond between the children and the nanny when it extends into adulthood can go as far as we’ve recently seen,” she added.

Royal expert Victoria Arbiter echoed Heren’s sentiments. She said that royal nannies have a very intimate position in the royal family because they’re involved in the children’s lives almost as much as the youngsters’ parents.

“William and Harry stayed close to all their nannies,” she said. “The thing that’s tricky too is when you become a royal nanny you are somewhat giving up your own existence. The nannies that looked after William and Harry were either widows or never married so there is as well trying to find the right person who is going to fit the mold who will be discreet. Also, who will put your child’s wellbeing at the center of their existence but is also happy to give up a huge part of their own life,” Arbiter added.

In the past, reports also swirled that Princess Diana was jealous of Prince William’s nanny Barbara Barnes. Royal correspondent Katie Nicholl said that the Princess of Wales was the one who convinced Prince Charles to hire Barnes. But the minute she saw how close Prince William and Barnes have become, she decided to sack the nanny.

Prince Charles, Prince Harry, Princess Diana and Prince William Britain's Prince Charles (background, L), Princess Diana (C) and their sons, William (R) and Harry, leave the church of St. Mary Magdalene near Sandrigham House 25 December. POOL/AFP/Getty Images