Kate Middleton has paid the most touching tribute to Prince William‘s mother - and we love it!

Kate's style has always been one to admire, but last night called for something special. The Duchess of Cambridge wore a tiara to the annual Diplomatic Reception at Buckingham Palace last night, just the fourth time we've ever seen her wear a regal headpiece.

But this was not just any tiara. It's the Lover's Knot tiara, which was the late Princess Diana's favourite tiara, and was gifted to Wills' mother from Queen Elizabeth II on her wedding day in 1981 to Prince Charles. This is the first time anyone has worn the headpiece since Diana's tragic death in 1997.

The tiara was originally made for Queen Mary in 1914. It was her own design, from pearls and diamonds already in her family's possession, inspired by a tiara owned by her grandmother, Princess Augusta of Hesse, who married the first Duke of Cambridge, seventh son of King George III, in 1818.

After Mary died in 1953, the tiara was passed to Queen Elizabeth II, who wore it regularly until she gifted the tiara to her daughter-in-law.

BEAUTIFUL!