'My autistic son was violent and withdrawn. Then Henry the retriever arrived and saved my family'

At one stage, Nuala Gardner felt so hopeless about the future of her severely autistic son that she walked into the kitchen and starting preparing a fatal dose of painkillers and sleeping pills. Dale, then aged four, could barely communicate and was prone to violent, terrifying tantrums. In despair, suicide seemed the solution to Nuala.

"I thought I was never going to get the help that Dale needed, and that he would remain a severely 'handicapped' child whose quality of life was going to be horrendous," she says. "It was going to be a lifetime struggle and I just couldn't bear it. I knew it was going to kill me in the long run to stand back and watch the quality of life that Dale was going to have."

Fortunately, the sight of one of Dale's toys made Nuala think again. Soon after, she discovered the key that would free her son from his world of isolation: a golden retriever called Henry.

Dale was born with a misshapen head following a protracted labour. "As I was handed this baby I felt a surge of elation, but when I looked at his head I was horrified," remembers Nuala, 47, a senior community nurse. "Thankfully, from a medical point of view he was thriving, and I was told that it would settle down."

But Nuala and her husband Jamie's anxiety about Dale's head, which corrected itself, was replaced by something even more worrying. "Because he was a first child in the family, he was hyper-stimulated. We grafted for everything we could possibly get from him – eye contact and that crucial 'mamma and dadda' – and it just didn't come. His behaviour became horrific. The tantrums became battles and Dale's frustration escalated to constant head-banging just after the age of two. If I needed to leave the house, and Dale was locked into totally obsessive play, he would go absolutely ballistic at the interruption. He would scream, bang his head, bite, kick and lash out at me.

"A typical day would last 18 hours. It could be an hour's battle to get his pyjamas off, another battle to get him washed, another battle to get him dressed. Trying to get any form of sustenance into him was horrific."

Eventually, after many pleas for help, Dale was referred to a speech therapist. But his behaviour spiralled out of control. "As it went on, my mental and physical health deteriorated and I made a suicide attempt," says Nuala. "It was a cry for help; I was desperate. About a year ago, a mother with an autistic child in her arms jumped off the Humber Bridge. I know how that mother felt."

Dale's autism was diagnosed when he was almost four, after the Scottish Society for Autism put the couple, who live near Glasgow, in touch with an expert in Nottingham. "We got nowhere in Scotland. No one would take us seriously. I reached the end of my tether when a local consultant paediatrician was going to conclude that Dale had a communication disorder, and label him as a child with non-specific mental retardation."

The diagnosis meant that Dale was offered more hours at the language unit, and was then collected and taken to a mainstream nursery. "Even with all the right help, Dale's autism was so severe that had we not continued with it at home he would not have improved as he did," she says.

When Dale was about five, they visited relatives who owned two Scottie dogs. To his parents' astonishment, Dale started to play with them. "The dogs dropped the ball at Dale's feet so he knew to pick it up and throw it. Normally, this would take weeks of instruction. Because they were animals, all the threat of humans and eye contact was gone. We were delighted. Here was something very different – a happy boy."

Nuala immediately set about finding a dog for her son, and decided on a golden retriever. When the family went to a breeder, a puppy bounded up to Dale, who started to stroke it. Nuala and Jamie decided that he was the one. "From the minute the dog entered Dale's life, there was a gradual improvement," says Nuala. "Dale had a total connection with him. Henry was a living educational resource. Dale even looked at his eyes. Unlike humans, who bombarded him with language, towered over him and petrified him, Henry was a little bundle of fluff with eyes that said, 'Hello Dale, I'm here for you.'"

Dale used to control his parents' language, hating words such as "OK", "proud" and "alright". "One time I broke the rules and said them all in one go. I paid for it with a horrendous tantrum that I hadn't witnessed for a while," remembers Nuala. "I had to sit on Dale to stop his head banging and he ripped my shirt. Jamie came home and I said, 'Look, even Henry looks worried – that's how bad this is.' I think that was the moment of my husband's inspiration. He adopted an old, wise voice and said: 'Look Dale, it's Henry speaking. I'm worried about you, please don't do this. I want to go out for a run.' Dale immediately looked at the dog and said: 'I'm sorry Henry, let's go for a run.' He threw me off, grabbed the dog and went out."

His parents thought this about-turn was a one-off. Then, when it was time for the bedtime battle to begin, Jamie told Dale that it was time to put his pyjamas on. Dale replied: 'No Dad, speak like Henry.' Jamie said in Henry's voice that he wanted to go to bed, and to please put on his pyjamas. For the first time, Dale obeyed.

For the next three years the family communicated through Henry, with the blessing of a speech therapist. "The progress just accelerated with his school work, at home and his ability to socialise." Dale is now 19, has just completed a National Certificate in early education, and plans to work in a nursery. "He's a wonderful young man," enthuses Nuala. " He's a credit to us and a credit to people with autism."

Dale, too, is grateful. "Henry did a lot for me," he says. " He taught me how to appreciate other people and understand their feelings. He had certain expressions and I could get a picture of what he was feeling. Since I've got older I've realised just how much good he did me."

With the help of IVF, Nuala and Jamie had Amy, now seven. It was when she was staring at one of her brother's toys that Nuala suddenly realised she was autistic too. "It was if someone had walked on my grave. I thought, 'Dear God, here we go again.' When I tried to engage I was thinking: 'Where has my little girl gone?'"

Fortunately, Amy's condition is not severe, and she attends a mainstream school. She also benefited from Henry, who died two years ago. Dale still sleeps with the dog's collar under his pillow. "Henry is always going to be a major part of our life," says Nuala. "He will always be an equal member of our family. We call him Sir and it's totally and utterly appropriate."

A Friend Like Henry, by Nuala Gardner, is published by Hodder & Stoughton on 26 July at £14.99

Autism: the facts

* Autism is a developmental disability that affects the way a person communicates.

* People with autism struggle with social interaction.

* Their ability to develop friendships is generally limited.

* Genes may be a factor in the disability, and the National Autistic Society believes it may also be associated with conditions affecting brain development occuring before, during or very soon after birth.

* Dogs and horses are sometimes used to complement treatment for autistic people. Therapists work their goals into children's interactions with animals. Working with animals during therapy has been found to be calming and motivating for autistic people. Animals also help to hold autistic children's attention.

* Dogs and horses are the most commonly chosen therapeutic animals for autism work, although cats can also be used.

* Organisations in the United States provide families with dogs, which the autistic child takes to school to help reduce emotional outbursts and improve socialisation.

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