The woman pointed to two photographs of herself taken when she was a small child.
In the first she was smiling, bright eyed and bubbly, a picture of happiness. In the second, taken just a couple of years later, she looked withdrawn. The light has gone out of her eyes.
"Why did no-one notice?" she asked.She was taking part in a documentary film made by survivors of child sexual abuse. A handful of middle-aged women and one man looked back on their suffering and the blight it cast on their lives. It affected their personal relationships, marriages and ability to work. It haunts them still.
Judging by the avalanche of abuse revelations these past few months and years, their torments are all too common. And now we know the perpetrators are often the least obvious suspects. Rolf Harris? I would never have guessed. Would you?
First the churches were exposed, especially Roman Catholic priests. Now we have the Mother of Parliaments announcing inquiries into allegations of historic abuse. Has it, too, covered up members' culpability, as privileged institutions seem to do? In between, we've witnessed heads roll in showbusiness, Harris following Jimmy Savile into the annals of shame.
It feels as if a stone has been lifted up and the pillars of our society are tumbling. Sexual abuse has been exposed in private schools as well as children's homes. Paedophiles download child pornography from the internet. They lie in wait on social media sites.
This vile practice crosses boundaries of class, colour, nationality and race. Asian British men have been convicted of grooming vulnerable white girls. White British men go to Thailand to abuse children. Destitute parents in Cambodia have been selling their daughters' virginity to the country's elite. One mother who worked in a beer garden in Phnom Penh saw 50 girls being purchased "like they were delicious food".
These horror stories, for that is what they are, have a common denominator. In the vast majority of cases, the abusers are men.
Given the scale of the abuse that is emerging, it must follow that a sizeable minority of men, given the opportunity, will take predatory sexual advantage of the young and the vulnerable. And they will do so regardless of the consequences to their victims.
Does this inconvenient truth sit at odds with a debate about gender which likes to play down the difference and talk up the similarities? Is this the biggest gender divide of all, the unbridgeable gulf? Will we ever be able to make it go away? I don't think we will.
I knew that most child sexual abuse is perpetrated by a family friend or acquaintance. It can remain unreported or take many years to emerge; so what we are seeing reported is just a hint of what has been and still is going on.
What I hadn't realised was its prevalence. The NSPCC reported last year that almost one quarter of young adults (24.1 per cent) had experienced sexual abuse by an adult or peer during their childhood.
For 11 per cent, it involved "contact" abuse. The remaining 13 per cent was "non-contact", possibly being groomed and persuaded to perform sex acts over the internet.
It is also the case that being disabled triples a child's vulnerability to being abused. I'm not claiming that female sexual abuse is unknown but we can name the primary female predators of our age on one hand: Myra Hindley and Rosemary West being the most prominent. (And both were working with a man.)
Yes, women do sexually abuse children. Mostly, they do so at home. There is ongoing discussion about incidences involving women being under-reported. But it remains undeniable that the vast majority of predatory abusers are male.
It bewilders me. I thought I could see some rationale in celibate priests, often recruited to seminaries when they were just children themselves, developing in a perverted way. Their teaching involved seeing women as a threat to their priesthood. It excused nothing but it offered me some sort of explanation.
But when it comes to the leading figures of popular culture and now, perhaps, politicians in the House of Commons or the ermine-trimmed Lords, where fantasy can be indulged with other adults, what is the explanation? It can only be the gratification of twisted desire and the exercise of power.
We know there is a paedophile lobby that would wish for their condition to be "normalised". We must never indulge that argument. That would be normalising a practice that leaves its child victims prey to depression, eating disorders, self- blame, self-harm and, too often, suicide.
But there is a curious reluctance to be clear cut about the issue even at the higher reaches of professional understanding.
Internecine strife broke out within the American Psychiatric Association following a recent proposal to list hebephilia as a recognised condition in the Diagnostic and Statistical Manual of Mental Disorders. (Hebephilia is a sexual interest in children around the age of puberty: a Lolita syndrome.)
People concerned with the welfare of children would err on the side of safety. The argument about hebephilia has become critically important now that good nutrition means children reach puberty ever younger. But the motion was defeated.
We must take care that, while the age of puberty may drop, the legal age of consent must be upheld. I asked a lawyer friend what would happen if it were argued that an unhealthy sexual interest in children was innate in a minority of men.
He replied that the law doesn't punish us for what we are. It punishes us for what we do.
I find that comforting as I look around with new eyes. I know and fully accept that the vast majority of men are decent, normal people as distressed by child sexual abuse as any woman would be.
But I am also aware that no man, however charming, engaging and devoted to the young, can be considered risk free. It's a distressing thing to say but, unless we approach the protection of children with all our senses alert for danger, how can we better protect them?
Almost one quarter of children are currently slipping through the net of our combined blindness, of our naivety, of our trust.
Almost all women are strangers to the combination of sexual drive and narcissistic entitlement that must be necessary for the sexual abuse of children.
It's almost as if paedophiles belong to a different species. But it isn't true. They just belong to one extreme of a different gender.
We need to be careful never again to confuse the notion of equality with the mistaken belief that we are the same.
If we fall into that way of thinking, we risk lowering our guard when vigilance is the only protection we have.
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