Article continues below advertisementOK! can reveal Princess Diana once learned a painful lesson about royal restraint after a single hairstyle provoked fury from Queen Elizabeth II and quietly reshaped how the young princess presented herself for the rest of her life inside the monarchy.The incident took place in 1984, when Diana, then 23, attended the State Opening of Parliament alongside Prince Charles. Styled by her longtime hairstylist Richard Dalton, the Princess of Wales appeared with her short hair swept into an elaborate chignon that framed her Spencer family tiara.