Perfect match

You'd have to really love a character to carry on writing about him for 25 years. Otherwise it might start to feel like being stuck in a dull marriage.

Fortunately for US thriller writer Jonathan Kellerman, he remains smitten with his creation, child psychologist Alex Delaware, who first appeared in 1985's best-selling When the Bough Breaks and, 24 books later, is still helping the Los Angeles cops with their enquiries.

"I'm rather fond of Delaware," Kellerman says on the phone from New Mexico.

"He's been a good friend and changed my life in a wonderful way. I had no idea this was going to be such a long series when I started out but Delaware has proved to be a great vehicle to tell a story."

Back in the mid-80s, the Alex Delaware stories were considered groundbreaking stuff. Kellerman wrote about issues such as child abuse and featured a regular character who was an overweight gay cop. "That first book was a best-seller to everyone's surprise, not least the publishers," he admits.

More than 10 years previously the young Kellerman had started writing while he was also studying for a PhD in psychology. At 22 he managed to scoop a major literary prize - the Samuel Goldwyn Writing Award.

"I got an agent and thought I was hot stuff," he says. "But I was writing novels that weren't good enough to be published. I tried a lot of genres - humour, satire - but treated it more like therapy than a job."

Assuming he was destined to be a failed writer with a good day job, Kellerman established a thriving private psychology practice. Then one day he hit on the idea of writing a book about a character very much like himself. He gave him the same job, the same passions and interests, even the same dog (a French bulldog) although he admits that Alex Delaware is very much an idealised version of himself.

"I get mail from women saying he's so sensitive, such a good man," he laughs. "My answer is that I get to rewrite myself. I've been married for 40 years and like to think I'm a good man and husband, but I'm not perfect. Alex is my Walter Mitty fantasy in a way - he's younger, thinner and more physically fit than me."

The latest Delaware adventure, Evidence (Headline, $37.99) is very much a character-driven thriller as psychologist Alex teams up with his gay cop buddy Milo to help solve the mystery of a young couple found murdered in the half-built skeleton of a mansion.

"I write psychological novels with crime as a catalyst," explains Kellerman. "They're about the darker side of human nature ... Every book is more difficult than the previous one to write because I want to be original and keep it fresh. I'm working within the constraints of the series and genre but always trying to stretch the limits."

For a while he tried to maintain twin careers as a psychologist and author, writing in his garage every night from 11pm till 1am. But it proved too much to handle. In fact, when he had a brush with cancer at the age of 39 he struggled to do very much at all.

"I had a carcinoma of the thyroid so it wasn't life-threatening but it was still a slap in the face of my mortality," he says. "When I was writing Timebomb I was literally crawling to the office."

Kellerman survived to write more Delaware books as well as children's stories, non-fiction and some non-Delaware thrillers.

But the most extraordinary thing about him isn't the following he's built up or the number of copies he's sold, it's the fact he's inadvertently become the patriarch of a major American writing dynasty.

Wife Faye is a successful novelist in her own right, son Jesse has started turning out best-sellers and now his daughter Aliza has got in on the act, producing a young adult novel. "I met Faye when I was 18 and she was 21 and we married a year later," says Kellerman.

"She was a brainy maths type and I thought that was the career she'd pursue. She saw me struggling to write and then a year before I got published started writing a novel of her own, which got published straight away. I like to tell her she's not a proper writer because she's got no rejection slips ..."

Although he's proud to have children who are following in his footsteps, Kellerman is quick to point out they've done so independently.

"I guess when you have parents who are both writers some of that is going to get through," he says. "Our other two daughters are both pursuing PhDs in psychology. But it's not like I ever sat any of them down and tried to influence them."

This year Kellerman turned 60 (Alex Delaware is ageing a lot more slowly). He has a contract to write four more novels starring the child psychologist and would be happy to keep writing them beyond that.

"Retirement wouldn't be a good thing for me, I'd get bored, so I'd like to keep going but that depends on my health," he says. "Having had cancer at a young age does give you a sense that things can happen very quickly. And if I find the quality slides than I'll stop. I'd like to think I'd quit before I became a pathetic has-been!"