Her sister-in-law gets a lot of criticism for allegedly breaking royal protocol on a nearly daily basis, but Kate Middleton has also been guilty of the act in the past—including prior to her marriage to Prince William when the Queen herself made special arrangements for her to vacation with her then-boyfriend at Balmoral.

It has previously been reported that Queen Elizabeth allowed for Middleton to stay at Balmoral prior to her engagement to Prince William, which broke with royal traditions, where partners of unmarried royals were not allowed to visit with the Queen at her Scottish estate. However, her decision to allow Middleton to not only stay at the property but take photographs there, showed a touching moment where she decided to let the future Duchess get a glimpse at what she was really like—an opportunity she rarely afforded to others.

“As a woman who has lived her entire life in the public eye, the Queen rarely lets her guard down, and very few apart from her family and closest friends get to see the real Elizabeth,” Katie Nicholls wrote in the book “Kate: The Future Queen.”

As a result, it’s believed the visit was the starting off point for a warm relationship that eventually formed between the two, with body language expert Judi James revealing to Express UK that the women have a good relationship with one another and even exhibit some of the same qualities when it comes to their public personas.

“Kate was always a slow but steady integrator into the royal firm and her slightly traditional approach, making very few if any ripples in continuity, does seem to have resonated with the Queen, who increasingly appears to treat her as a friend as well as a daughter-in-law,” she said. “Like the Queen, Kate is an adept ‘masker,’ using body language techniques that appear to keep her inner feelings hidden.”

“Both women have perfected a social smile and non-verbal traits that ideal for the job they do but without encouraging any frenzied interest from the public,” she added. “You rarely if ever see either woman look anything other than pitch-perfect so we assume their lives are, too.”

Queen Elizabeth II and Kate Middleton Queen Elizabeth II and Kate Middleton arrive to visit Kings College, to open Bush House in central London on March 19, 2019. Photo: Getty Images/Niklas Halle’n