Imagine giving birth to a beautiful baby which, as the first months go by, appears to meet all the criteria by which the progress of "normal'' children are measured. He sits up, crawls and walks -- all within a reasonable period of time. He even begins to acquire language skills.

Then, slowly, things don't seem quite right. The child starts to withdraw, is easily upset, loses language and develops obsessive tendencies.

The worried parents begin a round of the experts -- doctors, child development specialists, speech therapists and more -- and are told: "Don't worry, he's just slow. He'll catch up. Some children take longer than others. Einstein didn't speak until he was three,'' etc.

Finally, the parents take the child to a specialist children's hospital for evaluation. Here, at last, someone makes sense of the anguished months of fear and despair. Their child has autism.

Immediately, thoughts whirl back to the Dustin Hoffman film, `Rain Man'.

"Surely, my child is not going to be locked into a world I cannot reach forever, is he?'' the parents ask.

"Not necessarily,'' the specialists say, "this is what you have to do.'' There then follows a long list of do's and don'ts, recommended therapy programmes, and more based on the child's degree of autism, and then they return home to begin long, demanding years of doing what it takes to help their child reach its maximum potential.

These are the stories of two families who are raising autistic children.