'She put on a heroically brave face...her love for her family shone but a dark shadow has been cast across their lives'

AGONY is piled on anguish. Disbelief gives way to despair.

- Leo McKinstry

It's almost impossible to overstate the sense of heartrending sorrow that will be felt at the terrible news of the Princess of Wales's cancer.

After all the hysterical speculation in recent weeks about her condition, much of it cruel, all of it ignorant, the truth about Kate's health is far grimmer than almost anyone outside her family will have imagined.

Yet even in the midst of the turmoil she must be feeling, she managed to put on a heroically brave face last night as she made her address.

Because of instinctive shyness, she has never enjoyed public speaking, but she gave an admirable performance as she talked stoically about the diagnosis and optimistically about her course of chemotherapy.

Her love for her family shone through, as did her gratitude to her medical team.

The power of her words was made all the greater by her obvious vulnerability, reflected in the occasional crack in her voice. Although intensely personal and full of raw emotion, the broadcast was honest, straight and phlegmatic, precisely the qualities that will help her on her difficult journey.

For all her refinement, there is a welcome streak of toughness about the Princess which may owe something to her forebears. Her paternal grandmother Valerie was a codebreaker at Bletchley during the Second World War, while on her mother's side, her ancestors came from Durham coal-mining communities.

Even so, the thought of what she, her husband, her children and her loved ones are now going through is painful to contemplate.

A dark shadow has been cast across their lives and all of them will need every ounce of courage and compassion to cope with the harrowing ordeal. But this is not just a distressing episode for her beloved family.

It is also a bleak moment in our national story, for Kate Middleton has been the best thing to happen to the House of Windsor in decades.