Kate Middleton has paid tribute to Princess Diana with her choice of accessories at Trooping the Colour. The Princess of Wales wore dazzling sapphire earrings that once belonged to her late mother-in-law.The 41-year-old wowed in a striking green outfit, with a dress designed by Andrew Gn and a matching hat by Philip Treacy. It is believed that the Princess chose the green outfit to pay homage to her role as Colonel of the Irish Guards.