Princess Anne has a reputation for her razor sharp wit and witty sense of humour. And she also enjoys a silly joke - as she once demonstrated at a Royal Family Christmas . The royals have a number of festive traditions they stick to every year, which includes unusual rules about exchanging gifts. In keeping with their German heritage, the family will open their presents on Christmas Eve rather than Christmas Day, and will opt for 'gag gifts' over more expensive luxury items. Speaking on Channel