Kate Joins the Queen – and 8,000 Others – for Tea
05/29/2012 AT 01:40 PM EDT
Under sunny skies and an uncharacteristically warm 77 degrees, she wore a familiar outfit: a hat by Jane Corbett and the same $2,000 pink Emilia Wickstead coat dress first seen 11 days ago at the Windsor Castle lunch the Queen gave for visiting royals.
Led by the Queen and Prince Philip, the royal party, including Kate, stood to attention for the national anthem before stepping down onto the garden's lawns.
Husband William, 29, was not able to attend – he's on duty in north Wales, where he is based with a Royal Air Force Search and Rescue squadron – but his grandmother did appoint him a new honor: With the title the Earl of Strathearn, he's to be a Knight of the Most Ancient and Most Noble Order of the Thistle.
As for Kate, amid the sound of small brass bands and some 400 staff members serving the invitees 27,000 cups of tea, 20,000 sandwiches and 20,000 slices of cake, she told guests she was "slightly nervous" about walking into a sea of faces.
"She congratulated us, and asked me how long I'd been in the RAF," Gareth Jones, 23, told PEOPLE about Kate's greeting to him and his new bride, Rebecca, just back from their honeymoon in Florida. "She seems to share a lot of empathy and genuine interest in people."
Also there was Sarah Burton, designer of Kate's Alexander McQueen wedding dress.
The garden party is a traditional highlight of the London spring-summer season, and Tuesday's event was the second of two being held at the Palace. The parties were started by Queen Victoria in the 1860s and have gradually evolved into a way of recognizing those who have played a role in public service.
Joining the throng were the Prince of Wales and wife Camilla, the Queen's daughter Princess Anne and the Queen's youngest son Prince Edward and his wife Sophie Wessex.