In an ongoing report of her son's battle with cancer, Mary Taylor sees him adapt to university life
"How's Greg these days?" "Oh, he's fine; doing well - putting on some weight. He's in his first year at Hull University."

Every time I give this reply I feel a twist of anxiety. Am I tempting fate? Is it true? And every time, I feel a secret glow, deep inside, flare up at the reassertion of a miracle. He has now escaped four death sentences.

Six years ago, when he was 12, my son, Greg, was diagnosed as having an osteogenic sarcoma (bone cancer) in his left upper arm. Subsequently, he has had secondary tumours removed from his lungs on three separate occasions, the last in the middle of his A-level course.

The fact that Greg is alive at all is an astonishing tribute to the power of modern drugs and the skill of specialist surgeons. The fact that he is now reading history at university is a tribute to him.

He attended school for about half his allocated time. The chemotherapy regimes he underwent were vicious. Often he had to leave hospital in a wheelchair, unable to stand unaided, so thin and fragile that he moved round the house like a wraith, appearing silently at the bottom of the stairs, unable for the moment to take the last steps into the room. Hating not having any hair but sick of wearing caps, he would come home, on those days when he did manage to get to school, shaking with exhaustion, wrung out by the noise and the people and the movement.

He was not easy to have in a class. Bald, white, scarred, frail, he refused to behave like an invalid and he was naughty; a boy of irrepressible wit. Day-to-day rules on the colour of his shoes, times of attendance, seemed irrelevant. How do you reprimand a pupil who looks like a ghost?

He has always refused to be an invalid - they all do. Sick children are special. Adults may exhibit courage and patience, but children who are dying refuse to be ill. They run wheelchair races, climb into canoes when one leg has been amputated, scramble down mountains, take their exams. They stagger off on holiday pressing the plaster over the chemotherapy drip hole with one hand, clutching the vomit bowl with the other. I never once heard Greg say: "I can't do this because I'm ill." Facing death head on, they seize life while it is given to them.

Applying to university was hard for Greg because in the preceeding holidays he had just had a sternotomy (opening the lungs by cutting through the breast bone) to remove a secondary tumour. He was so exhausted he couldn't make the permitted eight choices and submitted his application form with seven. He had corresponded with the admissions tutors from all his potential choices before the summer, testing their responses to him, warming to those who were the most helpful and encouraging.

What was he to put in the personal reference section? Not for him the Gold Duke of Edinburgh Award, the head boy or house captain's position of responsibility, the trumpet soloist from the orchestra. Refusing as always to make excuses, he stressed positive consequences of his illness: a sick child develops special talents; he learns to be alone, to be independent, to face the unthinkable, to capitalise on what he has, and above all to value the chance to learn, as this has nearly been taken away from him. And, like some underprivileged child in a poverty-stricken country, he has fought hard for an education. Not for him the repetitiveness of the classroom, compulsory regular attendance, inevitable progress to university.

Imaginative admissions tutors recognised this and gave him his chance. He chose Hull, in the end, for its course and he is there now, establishing his own little patch of history in a city unexplored by the rest of the family.

His room at home is empty. It carries glimpses of him - his books, his computer, the walls covered with rave flyers - but the spirit of the boy is not here; it is taking its first steps within university life, testing its power, extending its horizons. Already he has discovered the proximity of the ferry to Amsterdam; he has tasted the dizzying euphoria of bungee jumping off the top of a crane ("... and after all the work we've put into you!" says his consultant). He is forever hungry, for he has a six-year hole to fill.

For a long time I held him cocooned, watching every tiny change, the colour of the skin round his mouth, the unsteadiness when he stood up too fast; listening for his coughing in the night. It is a challenge for me, too, to release him from my care and to watch him emerge.

I know that this is the end, and not the end, of a section of his life.

It would be good to see this as the end of all childish things, but the cancer will not release him as freely as I have done, and he is still on three-monthly X-ray checks. I know there are dark places scarred in his memory, and the lines that sometimes frown on his forehead betray untold horrors. He has learnt a deep sympathy for others' suffering and developed a ferociously protective hardness around himself. But what fun he is! What a challenge he throws down at life to do its worst!

I guess you have a lot of people to thank, Greg. Oncology consultants, surgeons, nursing staff, some sympathetic and very patient teachers, endlessly loyal friends, a sister who loves you dearly. But in the end, this is your triumph and the whole world lies ahead of you.