To be perfectly honest, I’ve never been much of an atoner. Now, at 94, it takes an effort to move fast enough to catch up with long-ago transgressions.

But if there is anyone in the world to whom I owe atonement, it is my father, the noted German pediatrician, Gustav Tugendreich.

My introspection was triggered by an invitation to visit Berlin, the city of my birth, by Dr Bennie Kuntz, a tall, handsome 34-year old public health researcher at Germany’s prestigious Robert Koch Institute.

Unbeknown to me, he was writing a biography of my father. In groundbreaking research more than a century ago on the high mortality rate among young German children, he and Max Mosse showed how much depended on the social and economic level of the children’s parents — especially if the mother had to do menial work outside the home.

Dr Kuntz tracked me down through the German translation of a Father’s Day article I had written in the Jewish Journal — it was how he learned of my father’s death in Los Angeles in 1948.

The elapsed decades, and the fact that I had changed my father’s unpronounceable (for Americans) last name to Tugend, led him to doubt whether he would find me alive and coherent, but he persisted.

After two visits to Los Angeles, he reciprocated this year by inviting my daughter Alina and myself to visit Berlin. In a jam-packed five-day schedule we met German intellectuals, civic officials, the favourite professional soccer team of my boyhood and a passel of journalists.

One key event, and a trigger for our trip in the first place, was the laying of stoppelsteine — literally “stumbling stones”. Some 70,000 of these small brass plated cubes now mark the front of homes left behind by victims of Nazi terror throughout Europe.

Most of those commemorated in this, perhaps the largest decentralised memorial in the world, were Jews who died or were murdered in concentration camps. But also included are families like mine who left Europe before the Holocaust hit in full force.

This massive undertaking is essentially the one-man effort of German artist Gunter Demnig, who designed the cubes and personally implants them in front of designated homes.

Some 100 people attended our ceremony, in front of our old home at Reichstrasse 104, from one of Berlin’s deputy district mayors to the taxi driver who met us at the airport.

The event concluded with the distribution of the first copies of my father’s biography and, though Dr Kuntz was the author, a large contingent waved copies in front of me requesting autographs.

We were forging a genuine friendship with the ever ebullient and thoughtful Bennie.

But given our tribe’s rich history of (justified) paranoia, I wondered that if his grandparents, or great-grandparents, had met me some 75 years ago, would they have shunned me — if not worse?

Would I, as an infantryman in the US army, have tried to kill his grandfathers wearing German uniforms?

Both my parents were non-observant Jews — my earliest holiday remembrance was of standing around the Christmas tree with the governess, nanny and cook singing carols — but there was one line my father would not cross: when in 1911 he was offered the directorship of Germany’s royal institute for infant care on condition that he convert to Christianity, my father declined.

He went on to serve four years in the kaiser’s army in the First World War and, in 1931, was publicly recognised as one of the 100 leading German physicians of the preceding century.

Suddenly, two years later, he found himself stripped of his honours and means of livelihood, forbidden to treat “Aryan” patients.

In 1937, my father was the first of the family to emigrate, initially for one year to England and then to the United States, and was safely abroad when Kristallnacht led to the first mass incarceration of Jewish men in concentration camps.

But his expulsion from the land of his ancestors and professional standing broke my father spiritually and physically.

And that was largely the picture I retained of him from our reunion in America in 1939 — four months before the outbreak of the Second World War — until his death in 1948.

While I was still in Berlin, I was too preoccupied with the fortunes of my boyhood soccer career and my favourite professional teams to take notice of his misfortunes and agonies. This insensitivity became only more pronounced when my mother, sister and I rejoined him.

My father’s heavy Teutonic accent embarrassed me; one particular incident still haunts me. One afternoon, I baulked at my assigned task of watering our small lawn, telling him: “Why don’t you do it. You’re not doing anything anyhow.”

Something snapped in my characteristically quiet and restrained father and, even with a heart condition, he tried to chase and beat me in a violent rage.

Looking back, my Berlin trip ended with a paradox. I can forgive a nation that in general seeks atonement for the sins of its fathers, but it is perhaps harder to forgive my teenage self for what I did not do for my father.