Through a personalised kindergarten programme that includes speech therapy, physiotherapy, occupational and music therapy, toddlers take steps to catch up with other youngsters their age and parents come to have some hope for normality.

Each year, an average of 82 to 85 per cent of Watchdog graduates are integrated into mainstream school settings with special needs support. 'Our mission is to help our kids reach their full potential as quickly as possible so they can be as productive as they can be,' says Abigail DeLessio, Watchdog's development director.

Just less than half of children at Watchdog have autism, a complex developmental disability caused by abnormalities in brain structure or function that affects a person's communication abilities. Another 40 per cent are developmentally delayed, which means a child, due to chromosomal and/or structural brain abnormalities, is slower to achieve key developmental milestones.

A much smaller portion of children suffer from Down's syndrome or cerebral palsy.

Though scientists may differ over the cause of the two most prevalent conditions - autism and developmental delay - they agree that there is nothing more important than early diagnosis and intervention.

'Once a diagnosis of special need/developmental delay has been made, it is important that intervention occurs as soon as possible. Generally, children learn developmental skills in a consecutive fashion - if the primary skills are not learned, it can impede development of more complex skills. Also, early intervention helps a child advance in all areas of development,' says Mrs DeLessio.

Though government-run maternal and child health clinics are the places most likely to identify children with special needs, Stella Wong Wai-mui, Watchdog's executive director, says there are signs parents should be on the lookout for in order to ensure any problems are detected as early as possible.

Abnormalities, explains Ms Wong, are most obvious when children are compared with their siblings or peers, although this can be difficult for first-time parents who have no frame of reference. Broadly speaking, parents should ensure their child is meeting all the key developmental milestones that address communication, understanding and learning, sensory and physical development and behaviour relating to others, Ms Wong says.

These, for example, include being able to pull themselves up by 10 months, speech by the age of one, walking well by 13 months and capable of putting on shoes, socks and pants by the age of two.

'Other signs parents should look out for include lack of eye contact, emotional instability, delay in speech and other unusual behaviour,' Ms Wong says. 'The first three years of a child's life are critical for learning and any problems are usually identified during that time.'

Though diagnosis is the best solution for the child, this is often hardest on parents who have to deal with crushing heartbreak.

'Parents' first reaction is often shock, confusion and denial. They feel helpless because they feel all the hopes and dreams for their child are gone,' explains Ms Wong.

'This can create tremendous stress for the family depending on the severity of the child's condition, the support services available and the financial situation involved.'

Marie Kenny was devastated when one of her twin daughters had been diagnosed with autism at the age of 20 months.

'At first you don't really believe it,' she says. 'I am still trying to accept it and keep hoping for a miracle although I know I need to accept it for my daughter's sake.'

The mother of two had to quit her job following the diagnosis, because her daughter - now 31/2 years old - requires constant care.

'Even at kindergarten, she requires a shadow to point her where to go. As a parent, a special needs child is all-consuming and so very stressful,' she says. 'I am with the kids all the time.'

The ripple effects of a diagnosis can also reshape the relationship between the spouses and the parents and their other children in the family because the special needs child becomes the focus of attention.

'Parents need to be sensitive to all their children and allocate time fairly otherwise the siblings may get jealous,' says Ms Wong.