Kate Middleton and Queen Elizabeth II shared a special bond.

When Princess Kate first joined the royal family for Christmas, she impressed the Queen with a thoughtful gift.

The Queen was disappointed when Prince William and Kate briefly separated in 2007.

Princess Kate recently paid tribute to the late Queen Elizabeth II during an official engagement in Windsor.

Kate donned a crimson double-breasted coat with black gloves, the same attire she wore to William's Sandhurst graduation in 2006.

Kate's brooch, similar to one worn by the Queen, held sentimental meaning.

The brooch was originally gifted to the Queen by the Welsh guardsmen.

Replicas of the brooch have been made, with Princess Diana and Camilla wearing similar styles.

Kate's decision to wear the brooch was a sweet nod to the late monarch.