But few, if any, respond quite so comprehensively as Ken Thompson.

To understand his story fully, we must go back to 2006.

Mr Thompson had become deputy commissioner of the New South Wales Fire Brigades after a highly distinguished 37-year career as an officer.

He had a great house in the northern Sydney suburb of Hunters Hill, which he shared with his wife Melinda and their healthy, playful two-year-old son.

But it was all about to end as Ms Thompson began showing the first signs of mental illness.

The symptoms were subtle at first.

But they progressed, manifesting themselves in paranoia and false beliefs about various people, including Mr Thompson.

"I didn't realise it at the time, but it started slowly and just escalated, it was terrible," Mr Thompson said.

By December 2007, his wife had been diagnosed by one of Australia's leading psychiatrists as having a paranoia disorder, and left their family home on January 1.

She fled the country with  three-year-old Andrew on April 24 after fearing she would lose access to him over the psychatrist's report.

The Australian Federal Police issued a warrant for her arrest and together with Interpol managed to trace her to Frankfurt, but there the trail quickly ran cold.

"I just didn't know what to do," Mr Thompson said.

"I had a job that carried with it a great amount of responsibility, but which I could no longer do properly. I couldn't concentrate.

"I felt like I couldn't do the job justice."

So he took early retirement and began to plot a way to find his son.

A close family friend, who does not want to be named, picks up the story.

"He was sitting in Australia as the police did as much as they could," she said.

"But it got to the point where he thought, "well what can I do?"

"And he knew he could cycle.

"I don't think he'll mind me saying this, but he wasn't the fittest person in the world at that point and he'd suffered a bout of pneumonia in 2008 that he'd had to fight back from.

"He had been under tremendous stress because of it all."

By that point the Family Court of Australia had granted an order lifting a ban on Andrew's name being published, to aid the search.

Mr Thompson got himself fit, organised a bike, set up a website, got a cycling shirt printed with Andrew's face on it and set off for Europe.

His plan was to cycle across the continent, searching everywhere he could for his wife and child.

He landed in London in early May this year, just in time for International Missing Children's Day on May 25.

Then Mr Thompson's real work began.

After cycling to northern England to spread the word about Andrew, Mr Thompson pedalled south, crossed into northern France, and cycled east through Belgium, Luxembourg and into Germany.

He visited Frankfurt and other German locations where Ms Thompson may have been hiding, before moving north again to the Netherlands.

There he handed a letter to the International Court of Justice in The Hague, signed by about 70 families of missing children, calling on the United Nations to update its 30-year-old conventions on child abduction.

Mr Thompson then pedalled back to Hamburg and Berlin, to Poland and then back to Germany.  On Wednesday was in Zittau, on the Czech Republic-German border.

He now plans to cycle to Prague, then to Switzerland and south to Spain, Italy and beyond as the northern winter draws in.

All the time he'll be looking for Andrew, looking for his wife and highlighting the plight of missing persons everywhere.

When will he stop?

"I don't know. I'll keep going as long as I can," he said.

"I'll do whatever it takes. He's my son. I'm responsible for him. I miss him, I love him. I'll just keep going until I find him."

SOURCE: THE COURIER MAIL NEWSPAPER - Brisbane
URL: http://www.couriermail.com.au/news/world/dad-cycles-europe-in-desperate-search-for-son/story-e6freoox-1225910835975

Reported by:
Miles Godfrey
From: AAP
August 27, 2010 11:15AM