By Alicia Brunker
Updated Jul 15, 2018 @ 1:30 pm

While it's reported that sister-in-laws Meghan Markle and Kate Middleton aren't BFFs, it looks like their bond is extending beyond their royal connection since spending time together at Wimbledon on Saturday.

The proof is in the pictures, according to body language expert Judi James. "The amount of spontaneous mirroring, plus the very congruent expressions of happiness and excitement on their faces signaled a growing friendship between the two women," she told The Daily Mail.

Celebrities Attend Wimbledon
Credit: Karwai Tang/Getty Images

It was previously stated that the Duchesses are friendly, but not attached at the hip, because of their distinct personalities. "I do hear plenty to suggest that they’re quite different people and that have quite different interests and that Meghan is quite independent and very confident and very keen to I think establish her own network of friends over here in London,” royal insider Katie Nicholl once told InStyle.

But what a difference a single day can make. At the Ladies' Single Finals, where Serena Williams faced off against Angelique Kerber, Markle and Middleton appeared like long-lost pals, and it wasn't just for the camera's sake.

Kate at Wimbledon embed
Credit: Clive Mason/Getty Images

James suggests that they genuinely enjoyed each other's company based on their facial expressions. "The rounded 'apple' cheeks plus the crinkling round the corners of the eyes showed the happiness to be the new royal double-act was mutual and genuine."

She added: "Kate is the royal with the pitch-perfect smile and that was very much on display, but the more regal aspect did relax several times with Meghan."

Celebrities Attend Wimbledon
Credit: Karwai Tang/Getty Images

A few times during the tennis match, Meghan stifled a giggle from Kate (a role usually reserved for Meghan's husband, Prince Harry), helping Kate feel at ease. "Harry has always been keen to make his sister-in-law relax and giggle more in public and it looked very much as though the confident and slightly more spontaneous Meghan might be taking on that role of her own accord."

The pair were also spotted leaning in closely to share secret whispers, which can signify "high levels of rapport and like-minded thinking," per James, adding: "[Meghan's] rather naughty smile and her hand-to-mouth whispering pose suggested shared fun and close exchanges."

Celebrities Attend Wimbledon
Credit: Karwai Tang/Getty Images

The Duchess of Cambridge was also keen on showing the new royal the ropes while offering subtle cues of protocol that Meghan "face-watched." "Royal newbie Meghan is clearly still learning on the job and her lower-key poses with Kate plus some of her face-watching signals suggested she was picking up protocol tips from her new sister-in-law," said James.

We have a feeling that these two will be leaving their husbands at home more often for some much needed girl time.