This includes stepping out with her father-in-law, Prince Charles, 71.
During such outings, body language expert Judi James explained the relationship between the royals.
She said Kate may have helped bring Prince Charles and Prince William closer together.
“William and his father haven’t always appeared to have the closest relationship with one another,” Judi told Express.co.uk.
“But with Kate present, the mood between the two men does seem to lighten.
“While the two men point and laugh open-mouthed to suggest there’s some kind of banter going on between them, Kate’s polite attention to Charles and her appreciative smiles as he chuckles suggests she might have mended a few bridges between them over the years.”
Kate is often thought to have a good relationship with her royal in-laws.
The body language expert explained that Kate, while in the Royal Family, may have played an important part in bringing them together.
Prince Charles is first in line to the throne, followed by Prince William.
If the Duke of Cambridge becomes King, Kate would also be given a new important title.
She would take on the role of Queen Consort, which would give her the same social status as the monarch.
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How did Kate Middleton become a royal?
Kate Middleton, or Catherine, Duchess of Cambridge, was born on 9 January 1982 at the Royal Berkshire Hospital, Reading, England.
She was born to Michael and Carole Middleton, a former flight dispatcher and air hostess. The couple founded a party supplies company, Party Pieces, in 1987 – now estimated to be worth £30 million.
Kate has a younger sister Pippa Matthews, 34, and a younger brother James Middleton, 31.
Kate and her family moved to Amman, Jordan, in 1984, where the future Duchess was educated at an English-speaking nursery school.
After moving back to Berkshire the family sent Kate to private school, St Andrews School. She went on to briefly study at Downe House before moving onto Marlborough College where she boarded.
For university the young Kate attended the University of St Andrews in Fife, Scotland. Here she was awarded an undergraduate MA (2:1 Hons) in history of art.
Relationship with Prince William
Kate met Prince William when they were both studying at St Andrews, and both living in St Salvator’s Hall. Famously, William reportedly took a fancy to Kate after she wore a see-through dress during a fashion show.
In 2003 the couple began dating and lived together during their second year of university.
The couple split in April 2007, however, in October they were back together.
Prince William proposed to Kate Middleton with his late mother Princess Diana’s engagement ring in October 2010. The couple were holidaying in Kenya at the time.
On 29 April 2011 they married at Westminster Abbey with a whopping 26 million watching the event live.
Kate wore an Alexander McQueen dress worth a reported £250,000 on the big day.
Kate assumed the title “Her Royal Highness The Duchess of Cambridge” and also became the Duchess of Cambridge on the day.