Princess Anne has been warned against “setting a precedent for future royal health updates” by a PR expert. The Princess Royal was discharged from hospital last week, where she spent five days receiving care, after being struck by a horse. Her husband, Vice Admiral Sir Timothy Laurence, confirmed that Anne is “recovering slowly” following the accident, and went on to praise the medical staff who looked after her at Southmead Hospital. Princess Anne, 73, suffered a concussion after suffering a blow to the head on the Gatcombe Park estate in Gloucestershire. No official photographs of the prince…