His new book, 80 Stories High: Uplifting Tales from Dr John's Humble Heroes, is a compilation of inspiring tales of ordinary people who achieved amazing outcomes for their family and community.

Drawn from people he met over six decades as a child psychologist, he says the stories "reassure readers of the power of love, courage, hope, determination, imagination and forgiveness".

He especially hopes to encourage seniors, who he says are often made to feel invisible, that "man-kind is not an oxymoron!"

The heroes in his book include Nada, who at the age of 55 begun hormone therapy so she could become the surrogate mother of her daughter's baby; Robin and Carolyn, who fought to provide a home for their late daughter's child; and Brodie, the out-of-control boy thief who went on to become a policeman.

"There are also a couple of stories about dogs who are heroes, just to give people a sense of hope and a laugh," Dr Irvine said.

"Because when you laugh, you release endorphins and build up immunoglobulin. So laughter is the best medicine."

Dr Irvine has written several books. The first, Coping With Kids, was based on his syndicated radio segments on 67 stations around the country.

The segments also advertised The READ Clinic on the NSW Central Coast, which he founded with his brother Warwick in 1981.

More recent writings include the WorryWoo companion books Helping Young Worriers Beat The WorryBug and Helping Young Children Manage Frustration and Anger.

Parents also know Dr Irvine from his regular appearances on TV shows such as Sunrise and Today, and as a popular guest speaker.

He said he and Warwick, a neuropsychologist, started the Erina clinic because at the time there were no services for children who were not coping at school.

"There was nowhere to go," he said.

At first, the clinic was founded as a "one-stop shop" connecting children with tutor/teachers.

"We diagnosed the kids, assessed them and set up a program for them, which we then reviewed to see how much progress we had made."

The clinic has since expanded to include services for a variety of issues, including pain, postnatal anxiety and PTSD management.

Today it is home to more than 30 psychologists, though Dr Irvine stepped back several years ago.

He said one of the reasons was that his hearing was starting to deteriorate.

"I couldn't hear the kids' little whispers into my ear, telling me their fears. It took so much bravery, they'll only do that once. You never get another chance."

He had also become increasingly frustrated at "warring parents who brought their children in for help but it was all about them".

A father of three and grandfather of six, he is well aware of the important role seniors play in the lives of their families.

But while many are delighted to help, he said, it's often help born of necessity.

Some help parents financially by babysitting, often going above and beyond by also covering additional costs such as school activity fees.

"But then that can come at a price because when you involve a grandparent, they're not automatons.

"They're going to have thoughts and ideas and they know what they think works. Things like 'Well, he doesn't play up for me', or 'I think you'd find if you just spoke less harshly to him...'

"It can develop quite a bit of friction between the parents and grandparents."

Dr Irvine says even though bringing up children is very different now, grandparents are still up for the challenge.

"For a lot of them, it's a sweet little deal."

Growing up in a religious family, Dr Irvine was instilled with strong Christian values that shaped his outlook on life.

While he no longer a church-goer, he still holds on to the core principles he said were ingrained in him by his mother - his own "humble hero" - during his early years.

He said these values have not only guided his personal life but influenced his work as a clinician and writer.

He believes in empowering his clients to find their own solutions and encourages them to think creatively and collaboratively.

Dr Irvine said parents often come up to him at the shops and thank him for helping their children.

But he says it is they who should be congratulated.

"I would say I might have been a catalyst but you had enough commitment to your family to bring that kid along to me."

Looking back on his career, Dr Irvine says children haven't changed so much as the world has.

"Children are the most adaptable creatures on the planet. Bar none. They come into the world as the only species that has 95 per cent of it not pre-wired.

"It doesn't matter where you are born, our brain is so flexible and plastic, it'll pick up and adapt to any environment.

"Kids' brains are much the same. Their milestones are much the same. It's the world around them that has changed so much."

He said that the best way to help children overcome their struggles is to tap into their problem-solving skills.

This can lead to creative solutions, such as the little girl with hair-chewing disorder who discovered Santa wouldn't see her unless she wore a red beanie to bed.

"It's about getting into the mind of the child. You can't help the child unless you can see into their life.

"And then you can explain to parents how they're seeing it and solve it together."