By Jennifer Newton With Christmas just weeks away, the royals will no doubt be preparing for their annual festive getaway to Sandringham. Each year, the Firm gathers on the Norfolk estate for their traditional Christmas celebrations, and for many years now, the Princess of Wales has been a firm fixture at the gathering. Nearly every year she is seen on the traditional walk to church and it appears that this year will be no different. But before her 2011 wedding, tradition dictated that before being married into the Firm, attending family occasions such as Christmas and Easter was off the cards…