This is one of the best memoirs I have ever read. Written by novelist John Niven, it begins on the day in August 2010 when he was told that his 42-year-old brother Gary was in a coma.

Gary had been admitted to hospital after self-harming. Then, left in a room on his own, he attempted suicide and was left brain damaged.

Niven recalls the excruciating days and nights spent watching over Gary, and his battle to get hospital management to admit negligence.

He admits to guiltily hoping that his brother will die, sparing their devoted mother from life as a full-time carer. The bulk of the book, however, looks further back, as Niven tries to work out how Gary’s life went so wrong.

He recalls their childhood and adolescence in Irvine, near Glasgow. Gary, who could “start a fight in an empty house”, was a serial truant, the despair of his respectable parents. 

Later on, he was unable to hold down a job and eventually went to prison for dealing drugs. He had a son with his ex-girlfriend whom he was not allowed to see.

It is a horribly sad story but leavened with John’s caustic wit. He paints a hilarious portrait of himself as an arty, pretentious adolescent who was even more of a mystery to his parents than Gary.

Unlike Gary, John worked hard at school and got a job in the music industry in London (as depicted in his brilliant novel Kill Your Friends).

But John was no paragon of virtue himself, mainlining cocaine for years, walking out on his wife and son, and stealing money from his girlfriend’s brother when he was nearly 40 as he struggled to make ends meet as an aspiring novelist.

Luckily, it worked out for him – which makes him feel all the more guilty about not doing more for Gary, whose suicide attempt was partly the result of debts that John could easily have covered.

This book is John’s way of making amends, a way of showing what was lovable about Gary without sugar-coating him.

It is a tribute to the sort of unglamorously off-kilter people, not really cut out for ordinary life, who are so rarely examined in books.

It had me hooting with laughter, rage and despair in turn.