I believe that it is a total irrelevance for the public to know what sort of man my father Patrick O'Brian was. The fact that he was a damn good writer should be enough. I remember that he wrote an article for a newspaper just before he died in which he dropped a pretty heavy hint, saying: "Do not seek to discover more about me. Just accept the stories for what they are." I think he was warning people not to go lifting up any stones, in case they didn't like what they found.

He would certainly have been aghast by the revelations this week contained in newly discovered archive papers. These document the bitter custody proceedings that took place between my father and my mother Elizabeth from 1944 to 1949, as they fought through the courts over my future. He would have been incandescent with anger that the public are now able to read his portrayal of my mother as drunken, illiterate and immoral, and her description of him as a cold and obsessive authoritarian who bullied and beat me regularly.

For my part, I do not remember anything from that time that relates to their dispute. It was all kept from me, and these revelations made me think about what my poor mum went through. As I see it, my father walked away from his wife, son and dying daughter, Jane, who had spina bifida. He left them with no money and just disappeared. How irresponsible can one get?

We had lived together as a family in Norfolk. I was five when he left us to pursue his affair with Mary, Countess Tolstoy, back in London. I have occasional memories of him taking me to Kensington Gardens around this time, and that is about it really. My relationship with him was cautious on my part. He was a bit of a stranger and I wasn't accustomed to him. I don't think he was accustomed to being with children either.

I went to boarding school, and shared the holidays between my mother and father. He had moved to Wales with Mary, to a very rural, out-of-the-way place. The house was OK, but the weather was awful - North Wales rain. I enjoyed some of my time there, but I didn't enjoy his company. I wouldn't actively seek him out to talk to.

In 1949, my father changed his name by deed poll from Russ to O'Brian. I was at school, and the headmaster simply told me, "Your name is now O'Brian". I do not know precisely why he did it, though I would guess that he wanted to drop all traces of his previous life and get on to another one. Around this time, my father removed me from boarding school, broke the custody agreement with my mother, and began to educate me at home. From my point of view he was teaching me mainly useless things. Arithmetic was OK. English was fine. But I couldn't see the point of Latin. He was a pretty rigorous teacher. He didn't like mistakes. If I made one, I would be told to put it right, and if I went on getting it wrong, he would cane me, but not heavily - don't run away with the idea that it was sadistic.

I got on much better with Mary, my father's second wife. She was a fine person - good fun, pleasant, an excellent cook and, on top of that, extremely good-looking. In the holidays I would go back to my mother, who was now living in Chelsea, and my boxer dog, Sian. I missed my mother terribly when I was away from her. The dog used to sleep on my bed, and I missed the dog hugely, too.

This went on for two years. I was living in a very remote area, and I didn't mix with other children, but a little boy out in the countryside can find his own entertainment. I didn't feel that I was missing out on a more conventional upbringing because I had no yardstick. Children are very resilient.

Later, my father moved to France and I was delighted to return to my mother. Over the years I continued to visit my father and Mary but our relationship didn't develop much further. He was not an easy person to get near. He was not affectionate; there were no quick hugs or pats on the shoulder. Nor was there much fun about him. Everything was a little bit heavy. He could also be very, very sarcastic. There was one incident that I remember clearly. He was extremely good at sharpening knives. "That looks interesting," I thought, so I had a go. His comment was: "I've seen angle-irons sharper than that." He could have thought of something pleasant to say.

I did have a sense that I was rather letting him down. I don't know how that came about, but I got the impression that he thought I was rather low-grade. I haven't a clue what kind of son he wanted.

He didn't talk about his writing very much. He just went off to his room and did it. I was about 15 or 16 before I became aware that he was a novelist and what that meant. I suppose I thought, "Good for him and let's hope it works, and quickly," because he and Mary were very poor indeed. I have read a couple of his books subsequently, but I certainly didn't rush out and buy every one as soon as it was published.

As I grew into adulthood, our contact dwindled further. I did my National Service and then returned to Chelsea. I did write the occasional letter but it was usually Mary who replied. Then, when I was 27 and about to get married, something happened that completely changed the way I thought about my father.

I had met a man at work, an ordinary Battersea guy, who had been in the army. I asked him how he could settle down in civvy street after all the excitement of war. He said he had three youngsters and that he had come home to find his wife dying of cancer. So he buttoned down and got on with it. He didn't walk away. And I thought, "Good on you. That's how a man should behave." It suddenly hit me that not all men behaved in the manner that my father had done. It gave me a big push to changing my name back to Russ before I got married. I was born a Russ and I wanted to be married a Russ. I didn't want to be part and parcel of a sham.

I got married in 1964. I have two daughters of my own now, two grandchildren and another two on the way. The way my father behaved has influenced hugely how I respond to them. Having had very little family life, I have consciously taken great note of how my wife goes about things and used her as a role model. She taught me patience, tolerance, calmness - loving is the word I am looking for. My children have both got degrees. One is a teacher, the other works in advertising, and they are good, rounded people.

My mother died four years ago. We were close up until her death. She didn't often refer to my father, but I remember once at a family occasion, with my wife and daughters present, she said of him: "May he rot in hell." I remember her tone of voice. She said it with venom, and it didn't surprise me. I think she felt hugely let down by him.

His profile is inevitably going to increase with today's release of the film based on his novel Master and Commander. He was a marvel at telling stories, and I have full respect for him in that way, but as a man he was not respectable.

When I changed my name, I wrote to my father. Mary wrote back, and I never heard from them again. She said she fully understood, and she apologised for writing my old name of O'Brian on the envelope through force of habit. She said it wouldn't happen again and it didn't, because that was the last time I heard from them. I made no attempt to get back in touch with them myself. It was a clean cut.