I first met Sherryl Jordan soon after my first YA novel was published. As I wandered into the Tauranga Public Library, where a Kids' Book Day was being held, a small comely figure with a gigawatt smile accosted me. 'Let me shake the hand that wrote See Ya, Simon!' That was Sherryl: generous, receptive, lit by eagerness and commitment.

Her struggles both professional and personal are almost legendary. A dozen-plus rejections before Rocco erupted into the world. Multiple health issues, including OOS so painful she could barely touch the computer keys, Chronic Fatigue Syndrome, a herniated disc, breast and then bowel cancer. Always, she battled on.

Descending Fire mentions all these. As the subtitle hints, it's not a conventional memoir. She writes in her Author's Note: 'It is more the autobiography of the people in my books... as real to me as friends I had known all my life... an insight into the many lives lived by an author as each book is created... the great joy of holding words'.

'Joy': that was Sherryl, too. She was unreservedly, almost unabashedly spiritual; had visions of events, of whole worlds, including one to follow this. She rejoiced in the moments when she felt she was 'writing from the heart of God'. One question every author gets asked is 'Where do you get your ideas from?' This book gives you Sherryl Jordan's answers.

So Rocco started after a story of medieval times wouldn't work, and she suddenly had a dream of a contemporary boy in a future, post-apocalyptic world. The Juniper Game began with her swelling interest in reincarnation, and then encountering a silver chalice in church. An anecdote about monks establishing goose farms for quill pens was behind The Silver Dragon. The Charlie Hebdo killings helped initiate The Anger of Angels. Absorbing revelations: they build a sort of literary archaeology.

You do get an autobiographical outline. She was born in Taranaki's tiny Normanby, had a crafty father who threatened to strap her beloved Teddy if Sherryl misbehaved. She wrote and wrote as a school pupil, and a teacher sent some of her stories to publishers (unsuccessfully). She was an excellent illustrator, working first with Joy Cowley, and struggled for a while to choose between that and writing. She married, became a Mum, tried all sorts of part-time work. An almost randomly-chosen CD of music inspired her.

After interminable rejections, she won the Choysa Bursary (anyone remember....?). Scholastic, thanks to splendid editor Penny Scown, took Rocco, with an offer of World Rights, and Jordan was away. She endured still more pain, disappointments, struggles with overseas editors – how dare a powerful character have dark skin? She was invited to write new Narnia stories, and all sorts of vilification poured down on her. Typically, she sees much of it as 'a liberation....a sublime joy'. That j- word again.

Using many extracts from her journals (the agonising death of her mother will leave you wordless), Descending Fire brims with details every author will recognise: the wonder and apprehension when characters set off in unexpected directions; the pleasure when disparate elements cohere; the fear when you finish that it may all be utter rubbish. And those rejections.

There's quietly practical advice for aspiring writers as well. Let the novel cool off before you revise; choose characters' names carefully; make sure your dialogue sounds authentic. All through, though she never says it with such vainglory, her stoicism, determination and faith endure. She was 'born to write', and she kept doing so. I thought I knew how hard she worked, but reading this, I'm astonished.

Sherryl died at the end of 2023. We miss her like hell. This modest, illuminating book helps explain why.

Reviewed by David Hill