You may have known Down syndrome as a genetic disorder that induces both physical and mental disabilities, with patients sharing similar features - a small chin, flabby muscle tone, a flat nose and a protruding tongue due to a small mouth and large tongue.

But what is it like to live with and raise a child with Down syndrome? China sees such an infant born every 20minutes, and an older mother is more likely than a younger mother to conceive a baby with the extra chromosome that causes the disorder.

In Eternal Son, Cristovao Tezza's award-winning autobiographical novel, the Brazilian author recounts the20-plus years shared between father and Felipe, the son. The book has just been published in Chinese by People's Literature Publishing House.

"I couldn't write it until I'd been with him for more than 20 years and reconcile with what has happened to me," says the 62-year-old novelist. "Once I began, I didn't need any notes. It all came exactly the way I remembered it."

He was 28 and expecting a son. The diagnosis was a shock and he refused to accept it, an almost classic case of denial. He would grasp at what little possibility there was for error, or a different chromosome behavior, or treatment to get his son "back to normal".

"Having a son changes anyone's life, and I have Felipe," he says. "Being a father means you have someone always dependent, always on your shoulder. It impacts very much on one's freedom."

The son had no sense of time, no yesterday, no tomorrow. At meals, he couldn't feel full, and would keep eating until his parents intervened. He was stubborn, had no control of his emotions and couldn't understand anything said in a passive voice.