In April 1995, Mr Maher's daughter Carmen died after she fell asleep at the wheel and crashed her car just five kilometres from home.

The tragedy came just 30 months after Mr Maher experienced his own close call.

He was seriously injured in a crash that killed an 18-year-old girl near Bendigo in 1993.

Mr Maher was not at fault.

He has since dedicated his life to educating young drivers about dangers on the road.

He has spoken to more than 450,000 students and almost 400,000 other people at corporate events.

Now, after decades of campaigning, Mr Maher has self-published a book with the help of the Warrnambool community.

Carmen's Legacy comes with a road safety message the author hopes will become part of the school curriculum for year 10 students.

Mr Maher said the book was partly funded by a GoFundMe campaign created in memory of Warrnambool College student Joel Moon, 16, who died in a double fatality at Winslow last year.

Joel and Kiara Drendel, 19, were killed when a vehicle they were passengers in hit a tree on August 26.

Mr Maher said he received a call from Warrnambool College the following day.

"Joel's sister Hannah had heard my presentation at the school in 2019 and she was apparently so moved by it she requested that instead of flowers, they would like all donations to be made to Carmen's Road Safety," he said.

"I couldn't believe it. I was so humbled."

The campaign raised more than $30,000 in 30 days.

Joel and Hannah's mother Jo said her family was passionate about helping John spread Carmen's story.

"We are beyond grateful to every person who made a contribution to that GoFundMe page because it has meant John can get his road safety message out to more people," she said.

"Maybe it will save just one other family from living his and our horror."

Mr Maher said while Carmen's Legacy was a personal story, it related to every single family.

"As I say in the book, what happened to our family isn't your story until it is," he said.

On the day of Carmen's death, she had driven her best friend to work at McDonald's.

They'd stayed up until 4.30am the night before talking.

"She was tired and on the way home our Carmen fell asleep at the wheel," Mr Maher said.

"She hit a tree and was killed instantly."

Carmen's sister Michelle was third on the scene.

She returned home with a police officer to tell her father his daughter had died.

Michelle stepped out of the police car with tears streaming down her face.

"It's Carmen, Dad. Carmen's dead," she said.

Michelle and her sisters Katrina and Jasmine contributed chapters to Carmen's Legacy.

"Michelle's chapter is particularly confronting because she was first on the scene and she knew Carmen had been tired," Mr Maher.

"She felt responsible for Carmen's death and we had no idea the depth of pain she carried until we read that chapter.

"I cried a lot but am really proud as Michelle and her sisters have added enormous value to the book."

Mr Maher said Carmen's Legacy was not only about road safety but mental health and the importance of family. He said he was incredibly proud to see it finally released.

"It took me 20 years to write this book because it was the hardest thing since burying Carmen," he said.

"Through my 50s and 60s, you've probably never seen a grown man cry so much. I can speak at any school, conference and international event without any problem but to put it in the written word was just so difficult.

"With every word I had to relive that very moment."

Mr Maher said fortunately the book allowed Carmen to remain in their life forever.

"And for that, we are the luckiest family," he said.

"Carmen has always been there when I give my presentations and now through this book, she will continue to be in our lives and of those who read it."

Carmen's Legacy will be launched in Warrnambool at a location to be announced on June 16.

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