The family has a long-standing commitment to the Royal Air Force with four generations of the family having served or trained with the United Kingdom's aerial warfare force, and many holding honorary ranks and patronages with RAF charities and associations.
The Queen has been joined by royal family members including the Prince of Wales and the Duchess of Cornwall, the Duke and Duchess of Cambridge and the Duke and Duchess of Sussex for a service to honour the RAF at Westminster Abbey. Appearances like this are rare for Kate, as she just welcomed Prince Louis April 23 and won't be doing public events regularly until the fall following her maternity leave.
This was an opportunity to meet RAF veterans, serving personnel and their families.
She wore one to Princess Charlotte's christening in July 2015 and repeated the look for the Trooping of the Color in July 2016 and a commemoration ceremony in Belgium in 2017.
Previously, it had been awarded to the top female cadet each year, but in 2015 the tradition was altered to give female cadets the same prize as male cadets, and the brooch was given to Kate.
The 36-year-old pinned the priceless piece on the fold of her pale blue Alexander McQueen coat dress.
They assembled on the palace forecourt to watch as The Queen made a speech and presented a new Queen's Colour to the RAF before heading back inside and out onto the balcony.
"Her father, his Majesty King George VI, was one of the founder members of the Royal Air Force".
The Duchess of Cambridge paused her maternity leave on Tuesday for a special occasion, close to her heart - literally.
Both women have found the style that works for them, which is encouraging us to find our own that we can always count on.