LIZ JONES: If the latest news about Fergie teaches us anything, it's that we should be kind and forgiving. King Charles learned that lesson well. Who knows what lies around the corner – for each of us?

They say bad news always comes in threes. Firstly, we heard that the Princess of Wales required abdominal surgery and will now take quite some time to recover.

The king has only just come out of hospital after treatment for an enlarged prostate.

And then came another shocking announcement. It was revealed that Sarah Ferguson, the Duchess of York, has been diagnosed with malignant melanoma – an aggressive form of skin cancer that can be caused by exposure to sunlight or the ultraviolet rays of tanning beds.

Those with fair skin are more sensitive. Women are most likely to have malignant moles on their legs.

This news comes soon after Sarah's treatment for breast cancer.

An Instagram photo of Sarah Ferguson. She went to recover at the Mayrlife Clinic in Austria after her second cancer diagnosis in a year

Sarah Ferguson enjoys the sun during one of her summer holidays

During reconstruction surgery after a mastectomy, several suspicious moles were removed for testing.

One came back positive. The diagnosis is serious, but the Duchess is said to be in good spirits. She is recovering at the Mayrlife clinic in Austria.

Her eldest daughter, Princess Beatrice, is patron of the British Skin Foundation, so is well used to talking to skin cancer patients and has no doubt offered both advice and comfort.

As soon as she got together with Prince Andrew, we all knew Sarah as Fergie. She was naturally more exuberant than her future sister-in-law, Diana.

There is rarely a photo in which she is not smiling. But she was never just the clumsy, slightly clumsy Joyce Grenfell figure.

She has raised two girls who seem completely sorted despite being members of the royal family. They have a career and their own family. They have never fallen prey to the endless criticism of their often bizarre sartorial choices.

The most telling thing is that Sarah has remained friends with her ex-husband through life. Since her breast cancer diagnosis, she has been very open and even braved ITV's Loose Women to encourage others to get checked.

No doubt this latest news will trigger a flood of people who, like Fergie, are fair-skinned and perhaps enjoyed sunbathing on holiday, sipping sangria on a sunbed (alcohol and tobacco can increase susceptibility to many forms of cancer).

The King's diagnosis has resulted in a huge increase in the number of men seeking reassurance, with the NHS website reporting 16,410 visits last Wednesday, up from 1,414 the day before. All of this makes me wonder why the Princess of Wales isn't more candid about what ails her.

It was Diana who, by talking openly about her eating disorder, was a pioneer when it came to breaking taboos around mental health. Even if one life is saved, it will be well worth the potential embarrassment.

The Duchess of York has raised two girls who seem completely sorted despite being members of the Royal Family. They have a career and their own family

Fergie surrounded by her loving daughters and Prince Andrew

Sarah was our surprise on Christmas Day when she walked to church with the royals

But my overriding feeling upon hearing Fergie's latest news is that it's just not fair.

She doesn't deserve another blow. How much more can a woman tolerate? Ridiculousness, divorce, scandal. The news that her ex-husband is being admired amid allegations of sexual misconduct is bearing fruit.

Can stress cause cancer? The causes are numerous. But the past few years can't have helped.

I am sure the King is very pleased to have welcomed Sarah back to Sandringham at Christmas. If this latest news teaches us anything, it is to be kind and forgiving. Because who knows what lies around the corner for each of us.