Kate shares a laugh with Sophie during Order of the Garter celebration

The Princess of Wales has joined other members of the royal family at one of the highlights of the monarchy’s calendar – a service celebrating the Order of the Garter.

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.

The Duchess of Edinburgh and the Princess of Wales chatted together (Yui Mok/PA)PA Wire/PA Images - Yui Mok

Kate 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 adding a summer picnic feel to the occasion.

The King and Camilla joined the procession (Yui Mok/PA)PA Wire/PA Images - Yui Mok

Kate and Sophie arrived together 15 minutes ahead of the procession and when two gentlemen ushers, who provide support at royal events, doffed their top hats one after the other at Kate and Sophie, the princess joked “again and again”.

The royal women looked stylish in wide-brimmed hats with Kate wearing an outfit by Self Portrait and a hat by Sean Barrett, with Camilla wearing a Fiona Clare dress under her Garter robes.

Before the service Charles hosted a lunch for the order, with the Duke of York among the guests but the disgraced royal did not join the others for the service.

Former prime minister Sir Tony Blair and Lord Lloyd-Webber are also Garter knights and processed in front of the royals with others.