Britain's Prince Harry and girlfriend Cressida Bonas will enjoy a private dinner at Sandringham tonight (27.12.13).
The royal and his 25-year-old partner will attend an organised "informal" festive party at the Queen's Norfolk estate and Harry's cousins, princesses Beatrice, 25, and Eugenie, who introduced him to Cressida, are also expected to attend.
A source told The Sun newspaper: "This is really important for Cressy. She and Harry have been dating over a year now and he is really serious about her.
"He missed her like crazy when he was away at the South Pole and couldn't wait to see her.
"She has been staying in Norfolk and as Harry was put in charge of organising this dinner, he invited her as a private guest."
The source added: "Many of the senior royals will have left Sandringham so it will be low key, but Cressy's invite to this dinner party is significant and should be seen as a major step for her.
"She is a great influence on him and they are very much in love."
Cressida spent Christmas with her father Jeffrey and stepmother Penelope at their family estate, which is situated close to Sandringham and it is thought Harry has already met the couple, along with Cressida's mother, Lady Mary-Gaye Curzon.
Harry, 29, met Cressida in May 2012 and began dating her soon after. They kept in contact via phone during Harry's 20-week posting to Afghanistan last year.
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