After Kate Middleton bravely revealed her diagnosis to George, Charlotte and Louis before sharing it with the world... MOIRA PETTY delves into how to tell children that you've got cancer

I can still remember the phone call that pierced my heart. It came from the mother of one of my three-year-old daughter's friends, and she told me, ominously, that there was something I needed to hear. 

Apparently, in the midst of playing, my daughter had announced: 'Mummies die but nannies don't.'

With such terrible childish candour, she had revealed an inner pain for which I felt crushingly responsible.

A few weeks previously, I had undergone major abdominal surgery, after which one of the hospital doctors had phoned to tell me I had a form of ovarian cancer.

I was 28 and the mother of one. But I suspect my first, panicky thought after that shattering news wasn't dissimilar to the Princess of Wales's: how to break the news to a child?

Moira Petty found out she had cancer aged 28. Pictured with her daughter

The Princess of Wales revealed on Friday how she had to reassure her young children following her cancer diagnosis

Pictured: Princess Catherine with her children George, Charlotte and Louis in a photo that was released for Mother's Day this month

Instinctively, we all know that protecting our young from a world of pain is the natural response of any mother.

In her video message, Kate emphasised that she had taken time to explain everything 'in an appropriate way' to her children, 'anxious to reassure them that I am going to be okay'. 

Naively, I thought I had done the same, assuming that, though bright and inquiring, at the age of three, my daughter was far too young to understand the implications of what might happen.

I explained that the doctors were going to make me better, but I'd be feeling a bit weak for a while, particularly following gruelling nine-hour surgery to excise the growth on my ovary, which had expanded quickly and weighed 8lbs when removed. 

Because of my age, doctors were able to leave the other ovary intact, preserving my fertility, while taking away 80 per cent of the affected one.

I would also be monitored with ultrasounds and blood tests, wary that the cancer could return to the remaining ovary.

My daughter visited in hospital and held my hand, walking me around the ward while I wheeled my drip. She seemed to be taking things in her stride.

The Princess of Wales pictured with her family at her last official royal engagement at the Christmas Day church service in Sandringham on December 25 

The Prince and Princess of Wales accompanied their children George, Louis and Charlotte for their first day at Lambrook School in Berkshire in September 2022

Pictured: The Princess of Wales attends the Together At Christmas carol service at Westminster Abbey with her husband Prince William and their children George, Charlotte and Louis, on December 8 last year

In fact, even though this unfolded in a time before the internet and social media underpinned our lives, it emerged I'd made the gravest error in thinking that a three-year-old was too young to understand about death. 

I assumed that because children can switch from talking about life-and-death matters one moment to something prosaic the next, it means they are coping well with bad news.

I wish I had not brushed it under the carpet, that I had taken the time to unspool every facet of what she might be thinking, to ally her fears.

Happily, over time, as my daughter saw me grow stronger and come back from each hospital check-up with a clean bill of health, her anxiety lessened.

It sounds like Kate has proceeded with infinite care in telling her children about her illness, taking all the time needed.

George, Charlotte and Louis will undoubtedly have had many questions and I'm sure they will continue. But clearly their mother is dealing with any worries – and will continue to do so – in a textbook manner.