There's no denying that the Duchess of Cambridge has a lovely relationship with her royal in-laws, particularly Prince William's cousin, Zara Tindall.
Since Kate began dating the Duke during their university years, she and Zara appear to have developed a close bond and have been pictured chatting and laughing on several public occasions.
SEE: Kate Middleton has a sweet relationship with her royal in-laws, including Prince Charles and the Queen - best photos
WATCH: Kate Middleton comforts Mia Tindall in sweet moment at Jubilee celebrations
The pair will have no doubt swapped wedding planning tips as the Cambridges and the Tindalls both tied the knot in 2011, and were guests at one another's nuptials. Kate and Zara have since become mothers with children of a similar age and the families have been spotted on playdates together.
William and Kate are parents to Prince George, eight, Princess Charlotte, seven, and four-year-old Prince Louis, while Zara and Mike have Mia, eight, four-year-old Lena and son Lucas, who was born in March 2021.
Take a look at the best photos of Kate and Zara's friendship through the years.
Kate was spotted in the stands at the Concert for Diana in July 2007 signalling that she and William were back together after a brief break-up. While the royal girlfriend at the time wasn't sitting next to her Prince, Kate and William's cousin Zara were pictured having a catch-up.
SEE: 16 lovely photos that prove the royals have a close bond with their cousins
When the Queen celebrated her Diamond Jubilee in June 2012, William, Kate and Zara sat together as they enjoyed the special concert put on at Buckingham Palace.
When Zara won a silver medal in the Eventing Team Jumping Final Equestrian event at the London 2012 Olympics, her family were there to cheer her on, including her BFF Kate, who waved and celebrated during the presentation.
SEE: 15 striking photos of royal history repeating itself
Zara made a beeline for Kate after the service to mark the 60th anniversary of the Queen's Coronation at Westminster Abbey. The Duchess was heavily pregnant with her first child, Prince George, at the time and shortly after the event, Buckingham Palace announced that Mike and Zara were expecting their first baby, Mia. We wonder if they were swapping pregnancy tips?
Kate and Zara enjoyed a day out at the polo in Tetbury in June 2015 with their firstborn, George and Mia. The cousins were spotted hugging one another as they arrived at the match and Kate even matched her young niece in a striped top!
SEE: 11 times royal parents doted on their children: from Kate Middleton to Prince Harry
We would love to know what Zara said to Kate to make her react like this! The pair are often spotted giggling together and always seem to have fun at Royal Ascot. The Duchess wore a white lace dress by Alexander McQueen for the occasion, while Zara looked lovely in an electric blue Escada ensemble.
READ: Princess Charlotte has the most adorable nickname for dad Prince William
The friends looked delighted to see one another at the Easter Sunday church service in Windsor in 2019 and even their pastel-hued outfits complemented one another's outfits.
Once again, Kate and Zara were spotted laughing and chatting at the races in 2019, with lots of hugs and kisses on the cheek as they arrived. The royal ladies donned blue-toned dresses, with Kate wearing an Elie Saab number and Zara opting for a floral Zimmermann frock.
Zara and Mike showed their support for the Duchess of Cambridge as they attended her Christmas carol concert at Westminster Abbey in December 2021. The couple attended alongside the Countess of Wessex, Princess Beatrice and Edoardo Mapelli Mozzi and Princess Eugenie.
Make sure you never miss a ROYAL story! Sign up to our newsletter to get all of our celebrity, royal and lifestyle news delivered directly to your inbox.