Margaret Pelling’s latest novel features Dora Clayton, whose personality fills a room. But behind her laughing façade is a troubled mind. Three years before A Diamond in the Sky opens, Dora’s baby daughter died at six weeks old — and the mother feels responsible.

The book was inspired by Margaret’s own loss — her second baby died of congenital diaphragmatic hernia in The John Radcliffe hospital after only nine hours, “We grieved, but moved on. Two years later, we had a beautiful daughter, Sally.

“While John is, and always will be, an unseen member of our family — Sally put some of her wedding flowers on his grave in nearby St Michael’s churchyard in Cumnor — we did not become stuck. I’ve mused from time to time on how it is that some who have an experience like this can accept it and move on, while others find it hard or even impossible.”

Dora is one of the latter, and Margaret writes about her with insight and empathy. It is Margaret’s second book; her first, Work for Four Hands was published by Starborn Books. A Diamond In the Sky is published by Welsh women’s publisher Honno, but the male characters and their problems are well defined. Inspirational teacher Tom Ross has been sacked from his job in a west London comprehensive for a forbidden relationship.

The reader is invited to ask if it is ever right for a teacher to have sex with a student. There is no hint of judgement in this powerful story. Compassion is the overwhelming emotion that weaves through the narrative and vivid dialogue.

One adult character, Larry, could have sprung from the pen of Mark Haddon. Larry is a social misfit with an intriguing voice.

Margaret read physics at Oxford, then took a doctorate in astrophysics, but her childhood love of writing was revived after the birth of her daughter.

“I wrote as a child — I was constantly making up stories. My imaginary worlds seemed so much more compelling than the real one. But the writing went underground when I fell in love with science, and university physics followed by the Civil Service meant writing was a distant memory by the time I was in my mid-40s.

“But when my then eight-year old daughter began writing in her turn, I said to myself, ‘Hang on — I used to do that.’ One day at the office, when a privatisation programme I was working on had drifted into the doldrums, I started writing a novel ‘under the desk’, just for the hell of it. I didn’t realise what I’d let myself in for! Within a week, I was hooked.

“The feeling that you could step into another world anywhere, at any time, with any bunch of characters that showed up in your imagination, was intoxicating. I left the Civil Service as soon as I could afford to.

“Luckily for me, a severance deal came along when the government of the day decided it wanted to cut staff numbers to save money. I think I was first out of the door. I now write full-time” said Margaret.

Her fictional teacher, Tom Ross, meets Dora at an astronomical club, brought together by her brother and his sister.

The diamond in the sky is Capella, in the constellation Auriga, and Tom explains why it is special: “There are other stars as bright or brighter, and there are plenty of stars much farther away.

“But what makes Capella special . . . it’s that in the depths of winter, when you’ve all but lost hope of spring ever coming, you look up and there she is.”

Margaret, now 63 and still a keen star-gazer, said, “What Tom says about the star Capella is drawn directly from my own feelings about that star, but the book’s title is also inspired by the mobile over the dead baby’s cot, which plays Twinkle Twinkle Little Star.”

Margaret will be one of an inspiring group of speakers at Kennington Literary Festival on Saturday, October 15, in Kennington Village Centre.

The programme and booking form is available from Kennington Library or from savekennington library.blogspot.com. Talks are free but The Friends of Kennington Library is offering £2 reservations to guarantee seats.

l A Diamond in the Sky is published by Honno at £8.99.