Royal biographer Lady Colin Campbell has claimed that Prince William and Kate Middleton are “coping as positively as they can” after the Princess was diagnosed with cancer. In her latest health update announced to the world, Princess Kate revealed she has begun “preventative” treatment after a test found cancer had been present, following her procedure. During Kate’s video message announcing her cancer diagnosis, she said that her husband was a “great source of comfort and reassurance.” Kate also said: “We hope that you will understand that, as a family, we now need some time, space and privac…