Queen Elizabeth, Kate Middleton
Queen Elizabeth II and Catherine, Duchess of Cambridge visit King's College to officially open Bush House, the latest education and learning facilities on the Strand Campus on March 19, 2019 in London, England. Getty Images/Paul Grover

Kate Middleton is a “slow but steady” integrator in the royal family.

Middleton’s relationship with her in-laws was examined by body language expert Judi James. According to the expert, Prince William’s wife has a warm relationship with Queen Elizabeth II, Prince Charles, Prince Harry and sister-in-law Meghan Markle.

“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,” James said of Middleton’s relationship with the Queen.

The Duchess of Cambridge and the Queen were seen together at Chelsea Flower Show. Prince William and Middleton welcomed Her Majesty with a kiss on the cheek.

James pointed out the Queen’s broad and authentic-looking smile that suggests warmth for the future queen. Meanwhile, Middleton showed genuine excitement at hosting her grandmother-in-law.

There are rumors that Middleton’s relationship with Prince Charles isn’t as warm as Markle’s. However, according to James, when Middleton is out with Prince Charles, the pair is very affectionate with each other. During their appearance at The Passchendaele Commemorations In Belgium, they showed their closeness by smiling and greeting each other with a kiss on the cheek.

Middleton’s closeness to Prince Harry is unquestionable. Prince William’s wife and brother have shared warm friendship over the years.

The Duchess of Cambridge and Duke of Sussex made a solo reunion sans Prince William and Markle on Anzac Day. Based on their body language, both were happy to be together.

“Harry was clearly having fun in Kate’s company, with their mirrored body language and their prolonged eye contact,” James explained.

“Their smiles were both matching and congruent, with rounded ‘Apple’ cheeks and eye-smiles and they were what is called ‘pinging’ smiles, meaning they seemed to bounce off one another.”

James added that Middleton also gets on well with Prince Harry’s wife. She pointed out how the two duchesses shared a real warmth during Commonwealth Day service where they used the “air-kiss” to signal genuine warmth between them.

Just recently, the Duke and Duchess of Cambridge and the Duke and Duchess of Sussex were criticized for their spending. Prince William and Middleton splurged $1.27 million for Kensington Palace’s driveway. Meanwhile, Markle and Prince Harry spent $3.05 million for the Frogmore Cottage renovation which was too much considering the number of homeless people in the U.K.