The recent deaths of Heather Wardle and her son James, 22 – whose decomposed remains were found in a suitcase at his home in Redditch in Worcestershire – highlight the inadequacy of provision for parents who find themselves chief carer for a disabled adult son or daughter. The full facts of this terrible story are not yet known, but it seems certain that Heather, apparently a devoted mother, was driven to despair by the huge burden of responsibility that falls on the “special needs” parent.

My own son George, who is autistic, has just turned 18. Fourteen of us celebrated with him at a local restaurant, and if space had permitted there could have been many more; George has always had lots of wellwishers in his life. But the average age of his guests was about 51½. With the exception of his little brother Jake, George is likely to outlive them all. Autism per se does not reduce your life expectancy: essentially, it’s an impairment of social and communication skills.

Despite their eccentric diets, George and my other autistic son, Sam, 16, are fit and well. I’m happy to carry on living with them at home for now – but what happens when, for whatever reason, I can no longer cope?

George is now officially an adult, but I won’t be giving him the key to the front door – because he has no independent social life – nor to the various locked cupboards in which I have to conceal precious or dangerous items as if he were still a toddler. He has made great strides in recent years – that he was able to sit and eat in a restaurant in a throng of people illustrates this – but he is still highly dependent and likely to remain so for years, perhaps for ever.

George talks fluently, but has never made a telephone call. He can read, but he has never followed a set of written instructions unprompted. He is able-bodied, but doesn’t perform the simplest household task. He has never crossed a road alone. He is absolutely devoid of common sense.

Some years ago, George was obsessed with supermarkets. I told him I would take him if he wrote a shopping list. He wrote “List”, and, underneath, simply: “I will see when I get there”. People often ask what the future holds for George and Sam, and I am still unable to improve on “I will see when I get there”.

Although George loves his special needs school and benefits hugely from the high staff-student ratio, he will have to leave school next year; I don’t yet know what he’ll do next.

School provision for special-needs children isn’t perfect, but at least in this country every child has a right to a place. It comes as a shock to discover that after the age of 19, your child has no right to any provision at all.

That’s not to say there is no provision. There are college courses, sheltered work opportunities, sheltered housing schemes. The chances are that I will find something appropriate for George eventually.

But many places are oversubscribed. If George doesn’t get a place, the answer will be: “Sorry, he’ll just have to stay at home and do nothing.” If luck is against us, when Sam leaves school in three years’ time, I could find myself at home caring for two highly dependent young adults.

Normal parenthood has a pattern. It’s hard work when the children are tiny, but before long they’re wiping their own bottoms and going for sleep-overs at friends’ houses; and in what seems like a twinkling of an eye, they’re off on their gap years, leaving their parents suddenly, magnificently free. My friends may look nostalgi-cally round their empty nests, but would they exchange their freedom for an indefinite future of constant vigilance and often hard physical labour?

When you’re a special-needs parent, you’re on call 24/7. My sons are now much easier to manage, but I still can’t leave them alone in the house, or take them to a public place without help.

In a typical evening, Sam might flush the TV remote down the lavatory, snip up a book with a pair of nail scissors, add a kilo of salt to the risotto I’m cooking and smash a vase of flowers. George, though less destructive, is just as aggravating. He will dirty six saucepans by carefully melting one square of chocolate in each, obsess about which pieces of litter can go in which receptacle and insist on cleaning the lavatory every time he uses it.

Despite the problems, I find them both funny, lovable and full of character. But I rely hugely on the seven hours’ break I get each day when they’re at school. That’s when I earn my (our) living. It’s also when I lead my own life, think my own thoughts, recharge my batteries.

Adult provision for George and Sam won’t be just about me, of course. Despite his autism, George is a social creature and needs more than just his family circle. And Sam requires the stimulus that a structured, well-staffed learning environment can give.

If I can’t find proper placements for my sons post19, the quality of all our lives will rapidly deteriorate.

My situation is not uncommon. One in 100 children are diagnosed with an autistic spectrum disorder, but local authorities seem woefully unprepared for the fact that these children turn into adults. I Exist, the National Autistic Society report based on the findings of surveys about autistic adults in England, discovered that 65% of local authorities don’t even know how many autistic adults they support. Added to that, 76% of authorities don’t have an autism training strategy, so support workers may not understand their clients’ needs.

Forward planning, better training, consistent support . . . local authorities could do a great deal to improve quality of life for this country’s 500,000 autistic adults and their ageing carers, among whom I will soon have to number my sons and myself. With the right kind of help, Heather Wardle’s tragedy might have been averted, and her three surviving sons would not be facing a motherless future.

For more information, contact the NAS helpline on 0845 070 4004 or visit www.autism.org.uk.

Charlotte Moore’s novel Grandmother’s Footsteps is published by Penguin

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