For example, she will frequent races such as Royal Ascot, and is on the guestlist for royal weddings and key calendar dates.

Kate, on the other hand, will regularly step out to represent the monarch.

She will also attend the races, wedding and important royal celebrations like her cousin-in-law.

Both women have a lot in common. They are both the same age and both have three children.

DON’T MISS

They also have some notable differences, according to body language expert Judi James.

She claimed Zara is publicly “tactile” while Kate is more “hands-off”.

Still, the expert suggested these differences have not been enough to stop Kate and Zara becoming close.

Analysing outings before the pandemic, Judi said: “In many ways, these two women’s body language should be a misfit.

She continued: “Kate’s expression as she looks back over her shoulder at Zara suggests genuine affection and pleasure, rather than any forced social smiling.

“Her smile is dimpled and her upper and lower teeth are visible and slightly edge-to-edge.

“[This] makes it look like a knowing smile of shared fun.

“Intense, exclusive eye-attention like this is also usually a sign that someone has just met a person they like and want to share a conversation with.”