Meghan Markle sought comfort in her prince and his brother on Christmas Day as she pulled off her first public appearance with the Queen and curtsy as a soon-to-be member of the royal family.

With an unsure smile and a firm grip on Harry's arm, the Californian actress emerged from St Mary Magdalene Church in a huddle of future in-laws.

As the Queen led the charge with Prince Philip standing closely behind, Markle stayed in her lane next to Prince William and her fiancé.

Unversed in the Sandringham Christmas Day order of events, Markle, 36, was put at ease by Harry and William who seemed to offer words of encouragement and pointers as they left the church, the Daily Mail reports.

Kate Duchess of Cambridge with Prince William and Meghan Markle. Photo / AP

Markle and the Queen met privately with Harry before their engagement was announced but had not been seen together in public until today.

She was photographed curtseying to the Queen before greeting well wishers outside the church with Prince Harry.

The pair then accepted bouquets from fans as they walked back to Sandringham House.

Among them was Judith Wallis, who was sitting in a wheelchair and is staying at the neighbouring Park House Hotel on her first Christmas Day visit to Sandringham.

Meghan Markle and Prince Harry greet well wishers. Photo / AP

She said Harry recognised her teddy bear called Maureen, which is a mascot for Armed Forces charity SSAFA, and her hat, which bore the Gurkha regiment emblem.

She said Markle spoke to them too and was "very very lovely".

Tess Gilder, manager of Park House, which describes itself as a unique hotel for disabled people, was with Wallis. She said of Markle: "She was just so natural, so lovely."

She added: "I think they just wished us a Happy Christmas and were interested in whether we had been before."

Emily Randall, 31, was first in the queue to get into the area by the church with her boyfriend Jamie Mackay, 42.

She said they set out from Chichester in Sussex before 10pm on Christmas Eve and arrived at Sandringham around 2am.

She said: "We thought it would be really busy. We looked online. We were the first ones here camping in the dark for two hours."

She said they had missed the Queen when she visited Chichester, so decided to make the trip to Sandringham.

Back at Sandringham House, the royal Family traditionally indulge in turkey, reared at Sandringham, before settling down to watch TV, including the Queen's Christmas speech.

This year, it is understood that Prince Harry and his fiancée will stay with Prince William and the Duchess of Cambridge at Anmer Hall, their home in the Sandringham grounds, rather than in the main house.

Kate, Duchess of Cambridge, Prince Philip, Meghan Markle and Prince Harry walk to the Christmas Day church service. Photo / AP

Markle will have to adjust to the royal family's idiosyncratic ways and customs, ingrained in centuries of tradition.

The royals exchange gifts on Christmas Eve, in keeping with German practice.

Markle is reportedly an animal lover but will have to put up the with royals' tradition of going shooting on Boxing Day.

The Queen arrived in a car and joined the group, which also included the Duke of Edinburgh and the Prince of Wales.

All four of the Queen’s children attended the service, along with the Duchess of Cornwall.

The royal family appeared to be in markedly higher spirits this morning compared to last year when the Queen was forced to miss the service while recovering from a heavy cold.

She and the Duke of Edinburgh had delayed their trip to the private Sandringham estate by a day after they became ill.