The rhythm of "getting on with life" after a sudden death is an elusive matter at the best of times. After four and a half years in which I lost my wife, my mother, my only son and my father, I have considerable experience of its waxing and waning.

- Jack Hanna, The Friendship Tree

ONE of the least appealing consequences of the multimedia age is the glibness of our attitude to tragedy, developed in response to the endless roll call of sadnesses that we daily encounter at arm's length.

Perhaps those who have read in the media of Jack Hanna's experiences found themselves less inured to tragedy than they suspected. Hanna, a former Irish Press sub-editor, married in 1970, and he and his wife Brighid had a son, Davoren, in 1975. It was some time before Davoren was diagnosed as having quadriplegic spastic cerebral palsy, but the couple soon realised that however severe their son's physical handicap, mentally his intelligence was enormous.

Davoren required 24 hour care. While several times he came close to dying, he began writing poetry, through a complex system of interpretative typing on Brighid's knee. His work won awards across Ireland, in Wales, and in the Observer Dermot Bolger published a collection, and Davoren found himself the focus of international attention, a celebrity.

In order to write, Davoren had to sit on his mother's lap in front of a typewriter and, with her help, stab at keys until she understood the word and wrote it for him. But in 1990, after 15 years, Brighid suffered a massive heart attack and died while on holiday with Jack in Donegal. Then in 1994, at the age of 19, Davoren died in his sleep. It is difficult to comprehend the devastation felt by their husband and father.

Jack has gone some way to articulate the loss in his forthcoming book, The Friendship Tree. which is published later this month. He has also just returned from climbing Kilimanjaro for charity. The sense of catharsis in The Friendship Tree is potent.

"I wanted to write about each of them they contributed such riches to my life, I feel blessed to have had them in my life so long. Death is a terrible blow to the heart, hut it is over two years now since Davoren's death and I felt it was the right time to write the book. We were very lucky. we lived in a house that was full of people all the time, Dav drew in all these young people, mainly girls, who filled our home constantly. it was a very joyful place sometimes. Other times it wasn't, it was very hard and Brighid got the worst of it in that I was out at work in the evenings. Then Davoren became a phenomenon, and we had to ensure he didn't become a freak show."

The book chronicles the couple's life together before and after the birth of their son. The strength of the bond between them comes across on almost every page, and with it the effect of their son's disability on their marriage.

"Brighid was a very strong woman, I value deeply those four and a half years we knew each other before we had Davoren. I wanted other children with great longing, and the ache of being unable to lasted all through our life together. Brighid was diabetic, and the chances of having another severely handicapped child were too great to take the risk. Brighid couldn't have coped with it, she always said it would have broken her. The physical strain of bringing up a child like Davoren is so great, I think it would have been physically impossible for her to have dealt with it twice.

"Once Davoren became well known, she was given this role of the martyr mother, which she hated. She struggled to place him in the scale of her life, not to let him become her only role. She went back to Trinity to do a Masters in Education, but the toll was inexorable I think, she never got the chance to tear herself away from Davoren's needs. She wanted desperately to hold on to all elements in her life. We didn't adopt a child, though we thought about it, but we thought the strain on the child would be too much it is hard to explain to what extent Davoren consumed our lives."

JACK'S account of Brighid's death and how he dealt with it makes for deeply moving reading. "I was at the end of my tether on a trip the two of us made shortly before the trip Brighid died on, I stood on the beach in Donegal and screamed and shouted, I was just at the point where it seemed so relentless, it dominated our life. My career had been worked in around Davoren, and everything that time seemed so impossible. Had Brighid died that time in Donegal, I think my guilt would have been very hard to bear. The night she died, I went back up the hill to the house, I needed to sleep in our cottage that night, and as I walked I felt this immense moment of clarity, I knew I wouldn't let it all come down on me, that Dav and I would bear it. That moment sustained me through many times later.

"It is still very hard. Each time I go away I think it'll be easier coming back, but when came back from Africa last week to the house, it was devastating. I hadn't expected it to be so powerful this time. I think the worst time, in terms of my own despair, was after the Irish Press closed. Having a job and the support of my colleagues helped me through after Brighid's death, but the hanging around the house really affects you. especially our house, which had been so lively and full of energy.

"What lingers in my own mind about Davoren is the incredible energy and spirit that came over him when wrestling to point to the letters, when he was writing his poetry. He would be so excited and vibrant, his gifts totally transformed him. I found some of his poems a bit precious, but I think there are some which are very special and the work of a great talent.

"All the young people he brought into our lives with his personality and his talent, we were very lucky. Brendan Kennelly met Brighid while she was at Trinity, and he gave Davoren's poetry a voice, he promoted the poems and read them aloud for us on many occasions, including Kenny Live. He wrote a lovely introduction to the book."

Hanna's future plans following his trip to Africa are uncertain. "Kilimanjaro was always a dream. I was watching a documentary about it and afterwards made some inquiries and it came together. It was an astounding experience, all the climatic zones in the world are on the mountain, and for me it was the fulfilment of a personal dream. Now that I'am back, I don't know what I will do. I went into journalism through an interest in writing, but it didn't come to very much. My real love is philosophy, that's what I'm trained in, but philosophy treats human beings as if they were never children, as if there were no parents, and no process of childhood. The whole world of nurturing was a part of my life for so long, and there is no room for it in philosophy, it is a blank. So I don't know where I'll go now. I've been writing the book, and that brought me backwards, I had to remember that life isn't primarily for the self but I had a debt to fulfil I wanted to honour the memories of two people I loved so much. I also wanted to tell the story to acknowledge the efforts of all the people who have helped us, and I dedicated the book to Davoren's young friends who gave us so much.

"There is nothing very much that is fixed in my life now that the book is written. I have another relationship, and I expect freelance journalism will be what I go back to, but have no certainties. Brighid and Davoren were such a big thing in my life, and I don't know where to move now I've to move on. They will always be in my heart and in the story of my living, but I want to move beyond it. I don't want Davoren's name stamped on my forehead forever. I want to have other stories to tell."