On a shortlist of parental horrors, having your child face a life-threatening illness is surely among the top three. I’m certain most of us squeeze our eyes shut and try not to think about it, but the other day I found myself thinking about Sally Roberts, the mother who tried to refuse surgery and then radiotherapy for her son Neon’s brain tumour.

Ms Roberts wasn’t convinced the treatment would work and feared the side-effects would be worse than the illness. After absconding with Neon and getting caught, last December she took her son’s doctors to court. Ms Roberts lost the battle to stop radiotherapy, and was excluded from any decision-making about Neon’s future treatment.

She turned up on LBC last Tuesday where she was lambasted on Nick Ferrari’s breakfast show for insisting that she was right to challenge her doctors’ view when her child’s life was at stake. She featured later on Julia Hartley-Brewer’s call-in as well, and whilst many callers presented as proof of their own emotional acuity the rhetorical pronouncement that a parent should ‘do anything’ to save their child’s life, it soon became clear that they didn’t really mean ‘anything’ after all.

For instance, they didn’t mean she should take him to a spiritual healer or make him drink green tea or have him swim with dolphins. Nor did they mean she should learn everything she could about his condition and treatment options so she could take an informed decision. Apparently, ‘anything’ meant unquestioningly accepting the doctors’ advice and suppressing her own anxiety and judgment. ‘They’re the experts, aren’t they?’ the host demanded repeatedly. By contrast, Ms Roberts was cast as a reckless and irresponsible flake.

This blind faith in expertise echoed the unsurprising position The Daily Mail took in December. With its populist heart reliably pumping hysteria about the meaningless and the mundane (always the thin edge of the wedge, apparently), in Neon Roberts’s case the paper urged us all to prostrate ourselves at the altar of authority. Specifically, The Mail revealed that it had called in an ‘expert’ who confirmed that Ms Roberts should heed the ‘experts.’ The mob did its bit in the comments section, shouting down anyone who dared to disagree.

I admit that I’m no expert, but the experience I do have tells me that the debate is less clear-cut than these smug certainties suggest. In fact, its horror lies precisely in its moral and medical complexity.

My sister died of breast cancer on 16th November 2011, two months to the day after my twins were born. She was 46. I live in the UK and she was in Toronto, so I couldn’t be part of the ‘inner circle’ who kept her company at chemo sessions, took notes and asked questions at oncology appointments, and sat for hours on her sofa, drinking tea and watching re-runs of Rhoda, an American sitcom we loved as kids. Instead, I did what I could which meant spending months researching clinical trials, alternative therapies, dietary considerations. I read books and articles, and spoke to doctors and researchers in New York and Beijing and Helsinki. I scoured online forums for leads and joined discussion groups. I prayed to a god I don’t believe in, and anyone else who might be listening. I would have done ‘anything’ to save my sister’s life.

The only expertise I discovered through her illness and treatment was in love and sorrow, but along the way I learned a thing or two about cancer.

I learned that it’s a fiendishly complex disease, that’s actually a whole range of diseases. I discovered that it’s fiendishly clever, too, and can quickly outwit the drugs designed to fight it. I read that some cancers are lethal by the time they’re detectable by any medical instrument. I learned that treatments such as radiotherapy and chemotherapy are crude and brutal, and some research suggests they increase the likelihood of metastases. (In fact, my stepfather had refused to join ‘the chemo club’ and survived the cancer he was assured would kill him.) An American researcher told me that aggressive, late-stage cancer is a highly individualised illness that ‘mass medicine’ lacks the capacity to address. And I observed that caring and well-meaning doctors are sometimes afflicted with an instinctive fraternalism that means they’ve got each other’s backs.

My sister told us often that she received good care at the Toronto hospitals where she was treated. She decried the contempt for the medical establishment of many alternative therapy proponents and practitioners, when it was researchers and frontline doctors who were ‘doing the heavy lifting,’ as she put it. She believed they were doing their best.

She died, so I remain unconvinced, but I often ask myself what I would do. The unsatisfying truth is that I really don’t know, and I’m rather surprised that so many people seem dead certain that they do.