Petronella McGovern is a friend of Liane Moriarty's, and the best-selling author better watch out

Every suburb has its secrets if you dig deep enough.

And now, thanks to former Canberran Petronella McGovern, we have our own mystery set right in the heart of the nation's capital. Six Minutes is the story of a missing child, set in the tiny village of Merrigang, which has more than a few things in common with Uriarra Village, and the repercussions the disappearance has on the community and those directly involved.

In a neat twist, McGovern and Moriarty are old friends who worked together in marketing at a business publishing company in Sydney.

"It was my first proper job after I'd finished uni and we've been friends ever since," says McGovern.

"We've always shared a passion for books, reading and writing. She has always been supportive and encouraging." (And has given the book a great review - "Impossible to put down and full of twists and turns you won't see coming! I loved this fabulous debut novel.")

Like Moriarty does so well, McGovern also wanted to examine human behaviour, how regular people behave under stress in extreme situations.

"I think we identify with the characters, we know them from our everyday life, and they give us an insight into how others are thinking and why they're reacting that way," McGovern says.

"These psychological thrillers, the 'domestic noir' genre, are closer to home, even inside the home. In real life, we're far more likely to have conflict with family and friends than with one of the villains from a James Bond story.

"While the situations, like a missing child or a murder mystery, are still unusual, the characters are people that you can relate to. The mystery in our everyday is more psychological, discovering other people's secrets and motivations, as well as understanding more about ourselves."

In the novel, Lexie Parker has just moved to Canberra with her husband Marty, a doctor working at Canberra Hospital. She's joined a mother's playgroup in Merrigang, still finding a way to settle into a new life and new routine. One fateful morning, she leaves her daughter Bella in the care of the other mothers while she goes to the shops to get some biscuits. When she returns, six minutes later, Bella is gone and none of the other mothers know what's happened.

McGovern said the seed for the story was planted when her then three-year-old son went missing in Questacon.

"Questacon's full of so many exciting places for a child to get into, he was always a very curious child who was always going off to look at things, I had the baby in the pram and he was just gone. Thankfully we found him after a while, he'd gone three stories up to look at the rockets or something, and a security guard tracked him down, but your worst nightmare as a parent is to lose your child," she says.

"At the time, I was part of a mothers' group and I started thinking about this idea of having that situation happen in a very safe place, where you're surrounded by supportive people you trust and how then the relationships would be affected."

Her children are now 16 and 14, but she said those early days with small children made her reassess a lot of things.

"It becomes tricky when you're a new mother. Before children I defined myself by work ... and then you have a baby and that doesn't matter," she says. "I remember in my first mothers' group we had to introduce another mother and I said this girl was with the Department of Health and she said, 'Don't say that, say I'm so and so's mother'. For me it was quite weird to suddenly define yourself by your baby."

Nevertheless this mothers' group became a great support network for McGovern.

"Sixteen years later we still catch up without the children, we have weekends away and dinners when we can. We've been through a lot of stuff together, it's been wonderful to have this group of women going through the same stages at the same time sharing their experiences."

The mothers in Six Minutes all respond differently to the disappearance, some not so positively.

"It's fascinating how four different people can have different memories of the same event," she says. "I think Lexie has internalised various beliefs that aren't necessarily true. And now she's living her life inhibited by those beliefs and fears. Lexie is judged by others, online and in person, and is made to feel guilt and shame for things that are out of her control.

"Judgement of others, particularly mothers, is a strong theme in Six Minutes. With our lives online and on show now, judgements seem to come thick and fast. Social media also seems to have encouraged the 'mummy wars', pitting different mothers against each other and amplifying judgement and criticism."

McGovern, 50, has her own writing and editing business and has also co-written two memoirs, but has always wanted to write a novel.

"When I was on maternity leave with my son, I started writing my first manuscript. It took a number of years and almost got to publication stage. That story was about a group of friends in their 20s," she says. "But as my kids grew older, I wanted to write about families and children. By then, I'd set up my own business at home and, with the children at primary school, I had a bit more time to focus on writing. I'd had the idea for Six Minutes for some time but to write it when my children were Bella's age would have been difficult and confronting."

McGovern moved to Canberra from Sydney in 1998, living in Chapman, Duffy and later Kambah with her husband and young family. She loved walking along Cooleman Ridge and up Mount Arawang and Mount Taylor, out to the Brindabellas.

"Those hills were really an inspiration for the village of Merrigang with its ridges and proximity to farmland and the bush. Living in those southern suburbs, the Brindabellas were always on my horizon," she says.

They moved back to Sydney in 2014, settling on the northern beaches, but Canberra is always close to McGovern's heart. "There's such a sense of community in Canberra, we get back as often as we can, I loved living in Canberra and I wanted the city to be at the core of this story."