Princess Diana was a trailblazer, a game-changer, a risk-taker, a let's face it and rule-breaker. These are great qualities in a lot of ways. They are not, however, qualities that the Queen always appreciates, especially in the moments when they motivated Diana to buck royal traditions the Queen did not think warranted said bucking.

The Queen was apparently frustrated by one of Diana's most iconic and creative fashion moments of her royal career. The fashion moment in question went down in 1985, when Diana and her then-husband, Prince Charles, were attending a gala dinner dance at the Southern Cross Hotel in Melbourne, Australia.

Diana paired her stunning green, satin evening dress from David and Elizabeth Emanuel with a royal heirloom: An art deco, emerald choker from Queen Mary that the Queen had passed on to Diana after she joined the royal family.

The Queen didn't mind that Diana was showing off the necklace (it was one of her favorites and she wore it several times over the years). She was irked by how Diana wore it—which was as a headpiece, rather than a choker.