At 12, I was in Auschwitz. My parents and seven siblings were murdered. Here is how I built a life

‘Do I believe in God? That’s a very good, dangerous question’ … Ivor Perl. Photograph: David Levene/The Guardian

We have only just met – I have barely sat down – when Ivor Perl confesses a profound doubt. “How much has it helped in the 80 years, us talking?”

By “us”, he means fellow survivors of the Holocaust who have testified to the horrors they witnessed. He wants to know if all the talks at schools, all the media interviews, have achieved anything. “Can you tell me?”