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 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 she needed to hear.

Apparently, in the middle of the game, my daughter had announced: ‘Mummies die but nannies don’t.’

With such terrible childlike frankness, she had revealed an inner pain for which I felt overwhelmingly responsible.

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

I was 28 years old and a mother of one. But I suspect my first panicked thought after that devastating news was no different than that of the Princess of Wales: how do you break the news to a child?

Instinctively, we all know that protecting our children from a world of pain is any mother’s natural response.

In her video message, Kate emphasized that she had taken the time to explain everything “appropriately” to her children, “eager to reassure them that I’m going to be okay.”

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

I explained that the doctors were going to make me better, but that I would feel a little weak for a while, particularly after a grueling nine-hour surgery to remove the growth on my ovary, which had expanded rapidly and weighed 8 pounds when it was removed.

Because of my age, the doctors were able to leave the other ovary intact, preserving my fertility, while removing 80 percent of the affected one.

They would also monitor me with ultrasounds and blood tests, fearful that the cancer could return to the remaining ovary.

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

In fact, although this was in a time before the Internet and social media supported our lives, it turned out that I had made the biggest mistake in thinking that a three-year-old was too young to understand death.

I assumed that the fact that kids can go from talking about life-and-death matters one moment to something prosaic the next means they’re dealing well with bad news.

I wish I hadn’t swept it under the rug, taken the time to unravel every facet of what she might be thinking, to piece together her fears.

Fortunately, over time, as my daughter watched me grow stronger and return from each hospital checkup in good health, her anxiety subsided.

It seems that Kate has proceeded with infinite care in telling her children about her illness, taking all the time necessary.

George, Charlotte and Louis will no doubt have had many questions and I’m sure they will continue. But it’s clear that her mother is addressing her concerns (and will continue to do so) like a textbook.