Former JC journalist Jem Lester is clear about the distinction between - on the one hand - himself and his severely autistic son, Noah, and - on the other- Ben Jewell, the protagonist of Lester's debut novel Shtum, and his severely autistic son, Jonah.
But it is a subtle distinction; the parallels are extraordinarily close. Both fathers, the actual and fictional, show enormous emotional dedication to their son and many of the episodes in the book, both funny and poignant, are directly taken from the author's own experience.
Crucially, Lester was able find the mental strength to write Shtum - in which he makes Ben's relationship with Jonah more draining than his own with Noah - because he has always felt secure in his demanding paternal role. When people ask how he came to terms with having an autistic son, he says: "I didn't have a huge problem dealing with it. By the time we got the diagnosis - he wasn't speaking and, at 15, he still doesn't speak - I already loved and worshipped him."
But what was draining in real life was the protracted and expensive tribunal appeal, launched by Jem Lester and his ex-wife, against their local council's decision not to subsidise Noah's place at a residential secondary school for autistic children. It is upon this that Lester has built Shtum's quick-fire narrative.
And it was always going to be a novel - not, Lester emphasises, "a misery memoir or a handbook on how to get through an educational tribunal. I did a masters in creative writing at City University, where the course director, Jonathan Myerson, said to me: 'I think you should write about autism'. I said no at first. I'd finished with the tribunal the day before I started the masters. I'd lost my parents in the previous three years. It had been a difficult time."
Moreover, he had to wrestle with his compulsion to underpin this serious subject with comedy: "I thought: 'if I'm going to do this, it's got to be funny'. I find it difficult to write things that aren't funny."
Certainly, Lester's work for the JC was often brilliantly funny, and he hasn't lost his touch. Ben's first-person narrative is laced with dark humour. At one particularly tense moment, he portrays himself and his father playing "nasty-look tennis". He describes his parents' marriage as "an endless ceasefire". And, seeking reading matter at a heavily burdensome point in his life, he declares Heart of Darkness to be "a bit light for my current tastes".
All typical Lesterisms, yet he remains eager to put distance between himself and his literary alter ego. "There are elements of me in Ben," he admits. "He's prone to depression and self-doubt. But, as I was writing, he very much became his own person. The level of frustration he felt in caring for Jonah, and difficulty in being alone with him, was not me. I've never had any difficulty in that situation."
Nevertheless, both real-life and invented fathers tried the same bogus remedy for their depression: alcohol. But, while Ben drinks his way through the novel, Lester had stopped drinking for eight years when Noah's appeal was lodged with the educational tribunal.
Lester's sobriety doubtless stood him in good stead during the long ordeal. "Noah's primary school was autistic-specific," he says, "and it was very good. But then, moving on, it was a problem. As an autistic child gets older, the harder it is to get a decent provision.
"Between myself, my ex-wife and her husband, we managed to get hold of the experts and, with some other help, to come up with the money that we needed. The whole tribunal process" - in which they achieved a positive verdict - "cost just shy of forty grand. The school is £200,000 per year. So you can understand why the local authority doesn't want to pay for it.
"For every Noah, who manages to get into a school like his, there's probably a hundred kids that don't. The strain on the parents and families is a disgrace. These children are silent because they don't have a voice. They have to have an advocate. It's easy for the powers-that-be not to do anything because these are vulnerable kids who aren't going to argue back."
Lester, who lives with his partner and her two children in north London, now sees Noah every other weekend - "in the week I'm not seeing him, I am miserable. Other kids go to boarding school but at least you can speak to them on the phone.
"We can now take him out to restaurants. We couldn't in the past. He is now using a fork. He doesn't use a knife so I'll cut everything up. When he's finished his meal, he will attack mine or those of others (a situation replicated in Shtum when Jonah steals a diner's salt beef). He thinks it's hilarious. The problem is, so do I. But nobody else in the restaurant finds it funny."
This is a truly devoted parent speaking. And when, on page 405 of Shtum, Ben tells Jonah that he is "the world's best listener. You never judge or contradict and I know that whatever I tell you remains sacred," it is clear that this is its author's message to his own, flesh-and-blood son.
Perhaps needless to say, the characters in Shtum are Jewish and, as with the humour, the Jewishness is natural and unforced. "I think," Lester reflects, "I was always going to write about what I know: autism and Jews."
'Shtum' will be published by Orion on April 7.
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