Princess of Wales all smiles at Order of the Garter Service

Kate, who missed last year's event during the period she was receiving cancer treatment, watched the procession of Ladies and Knights of the Garter through the grounds of Windsor Castle to St George's Chapel.

The King and Queen followed tradition and were at the back of the procession dressed in white plumed hats and dark blue velvet robes, as were the other members of the order including the Prince of Wales, Princess Royal and Duke of Edinburgh.

The princess was joined by the Duchess of Edinburgh and Vice Admiral Sir Tim Laurence at the chapel's galilee porch, a traditional vantage point to see the spectacle.

Kate (pictured) and Sophie burst into laughter just as the front of the procession passed by, with the elderly Military Knights of Windsor leading the way.

William looked across at the porch as he approached the viewing spot but his wife was deep in conversation with the duchess and when Kate finally looked up William was chatting to Edward walking beside him.

Their route was lined by troopers on foot from the Household Cavalry's Life Guards and Blues and Royals, wearing their plumed helmets and carrying swords.

The ceremony heralds a busy period for the royals with the King and Queen expected at Royal Ascot in the coming days.

Hundreds of spectators lined the procession route, with many bringing hampers and camping chairs.