By Russell Myers The deep bond between the Princess of Wales and King Charles will see them through this difficult time, writes Mirror royal editor Russell Myers. The royals have been through some tumultuous times in recent years but none will be as personally testing as this. Hospital admissions, test results and a dreaded cancer diagnosis for not one, but two, senior members of The Firm represents a truly unprecedented situation. But in the darkest of times it is, one hopes, the support and comfort of your loved ones that sees you through. The Royal Family, whatever your view on the collecti…