What's more, the source dished that the palace aides had to make sure the Duke and Duchess of Sussex's visit to the Queen's castle in Scotland did not coincide with the Duke and Duchess of Cambridge's, so as to avoid a potential row between the foursome.
"It can get quite busy at what they call 'the big house', and it's not especially relaxing even though it's a holiday," the source began.
"There's a daily routine which evolves around mealtimes, several outfits changes every day, sometimes five, and the Queen likes everything to run like clockwork.
"The focus is on being outdoors and in the countryside walking, grousing, fishing and hunting."
According to the Daily Mail, the feud began when Prince Harry took the drastic step of reading the riot act to his brother and sister-in-law when he felt they weren't supporting Meghan Markle ahead of their royal wedding last year.
Prince Harry then royally peeved off William and Kate when he announced he would have "two children maximum", on account of the environmental impacts of a big family - despite Prince William and Kate Middleton happily parenting three children, Prince George, six, Princess Charlotte, four, and Prince Loius, one.
Here's hoping the two brothers can work out their problems!