King Charles in major health update to friends and reveals 'determination' to beat cancer
![King Charles in major health update to friends and reveals 'determination' to beat cancer](https://i2-prod.mirror.co.uk/incoming/article32738592.ece/ALTERNATES/s615/0_Royal-Windsor-Horse-Show.jpg)
King Charles told friends of his 'determination' in beating his cancer in letters to friends, details of which emerged as the 75-year-old returns to public duties amidst his treatment