Princess of Wales Kate Middleton honoured her late mother-in-law Princess Diana as she attended King Charles official birthday celebrations, the Trooping The Colour. Kate Middleton attended the event wearing a fabulous green dress along with Princess Diana’s sapphire earrings. According to a report by Express UK, Kate chose a green outfit to pay homage to her association with the Irish Guards. The Princess of Wales is the Colonel of the Irish Guards, the role she took from her husband Prince William last year. She made debut as she appeared for the first time as Colonel. Earlier, King Charles took part in his annual birthday parade on horseback Saturday, the first time the monarch has ridden at the event since his mother, Queen Elizabeth II, in 1986. The annual Trooping the Colour parade marks the British sovereign´s official birthday.