For nearly three decades, Mrs Leong Geok Hoon led the frenetic life of a corporate high-flyer in banking and application management.

But two years ago, she pulled the brakes on her successful and lucrative career to be with her son while he studies for a degree in product design at the University of South Australia (UniSA).

The 59-year-old is not an overprotective mother, just an extremely supportive one.

Although 24, artistic and brilliant in mathematics and the sciences, her son Keat Mun is autistic and has problems with normal communication. Autism, clinically referred to as Autism Spectrum Disorder, is a lifelong neurodevelopmental disorder and is characterised, in varying degrees, by difficulties in social interaction, verbal and non-verbal communication and repetitive behaviour.

Although he was accepted by several universities abroad, with even one in the United States offering him a scholarship to do mathematics, Keat Mun could not get into any local institution. Mother and son settled on UniSA.

The decision raised a few eyebrows.

Mrs Leong says: "Many people tell me: 'You know your son is autistic, you know he may not hold down a job. Why are you investing so much in his education? What are you after? Glory?' "

Her answer is simple.

"I don't care what people think. I do know that if he wants to study, I will try my best to create the opportunity," says the congenial woman who has started a Singapore-based online business Adelaide Harvests selling artisanal produce she personally sources from Adelaide farmers and food producers.

Because of Keat Mun, Mrs Leong, who has three other children, has become a champion for autism awareness.

Affable and chatty, Mrs Leong has the serene self-assurance of someone who has squared off with the vicissitudes of life.

The fourth of sixth children of a petty trader and his hairdresser wife, she was given away at five days old to her paternal uncle and his wife.

This was on the instructions of her paternal grandfather because her adoptive parents then had only one child. The couple had another son several years after Mrs Leong came into the family.

"My (adoptive) mother told me about my background when I was 12," says Mrs Leong, who grew up with both her natural and adoptive parents and siblings in a kampung in Paya Lebar, in an attap house built on stilts.

Although emotionally confused then, it did not scar her.

"At least I was not abandoned or sold. It all worked out well. I have no issues at all."

Her family life was anything but vanilla. Money was always tight. Her late adoptive father - a bus driver turned contractor - also had a mistress with whom he had three other children.

When his mistress left him, he took them home to his wife who was so stressed that she suffered a stroke when she was just 38.

There were other troubles. Her younger adoptive brother was knocked down by a car and dragged for about 100m when he was seven. Among other injuries, the accident left him with a perpetually runny nose for several years.

Probably because of the upheavals, Mrs Leong learnt to be resourceful at an early age.

The former student of Fairfield Methodist and Raffles Institution breezed through school and financed her Business Administration degree at the National University of Singapore by giving tuition and applying for study grants.

Upon graduating in 1979 , she applied to be a management trainee at Straits Steamship although her friends told her the shipping company hired only males.

She became the first female management trainee in the history of the company, now defunct.

Fast, feisty and fearless, she quickly learnt the ropes of the industry, which was then dominated by males.

"I handled dangerous goods including radioactive cargo, bullets and guns. Due to security issues, the shipping could not be done in a port, so I would arrange for the container to be in the ocean, get a barge for the goods, arrange for a floating crane... I would then go out in a speed boat, climb up the container with the bill and loading documents," says Mrs Leong, who later became a key member of staff in the computing department.

At Straits Steamship, she met a marine engineer who became her husband. They tied the knot when he got a scholarship to study at the University of Surrey.

In the United Kingdom, she gained invaluable experience as a systems programmer for the National Health Service (NHS).

She worked in one of NHS' regional computer centres which managed various systems - from child help to blood transfusions - for 11 hospitals

Upon her return to Singapore in 1985, she joined Citibank. She was a vice-president when she left after more than 22 years, during which time she helped to design and launch, among other management projects, an online real-time dealing room system.

The pay packet and bonuses were generous but the work was demanding; she travelled often and sometimes worked 80-hour weeks.

In 2007, she took early retirement to be principal caregiver to her (adoptive) mother who was suffering from lung and brain cancer. Together with a helper, she lived with the elderly patient in a Toa Payoh flat for more than seven months, returning home only on weekends.

She next became a consultant with an international management consultancy. A few years later, she joined cosmetics giant Estee Lauder to oversee production systems in Asia Pacific, a position she held until 2015.

Thanks to a supportive spouse and in-laws, Mrs Leong is one of those rare women who managed to juggle a successful career with motherhood.

She has four children. Her twins, conceived through in-vitro fertilisation (IVF), are now 27; one is a civil engineer, the other a sound engineer. Her third daughter is 25 and a business analyst with consulting firm Accenture.

Keat Mun is her youngest child and only son.

Mrs Leong describes him as a happy baby although she noticed that he avoided eye contact and did not cry even when he fell and hurt himself.

"When he wanted something, he would take my finger and point," she recalls. "He could spell hippopotamus at a very young age, and he would cut letters of the alphabet and line them up on the floor, but he would not talk."

She broke down when he was officially diagnosed as autistic at three.

"I didn't know what it really meant. People just told you there was no cure," she says.

She bristles when recalling an encounter with a GP in Toa Payoh.

"He said: 'You know that your son is not completely normal and will always be like that. He falls between the cracks; he has IQ but is not normal. By the way, you don't need to bring him back to me, not even for other check-ups.' "

She adds: "I said to myself: 'My son might not be normal but mark my words: One day, my son might be teaching your son.' I was not going to give up, I was not going to let that change everything."

She didn't. She set out to learn as much as she could about autism to help not just her child but others with the condition.

She approached the former principal of Maris Stella Kindergarten, Sister Marjorie, who put Keat Mun in a normal class and employed a special needs teacher as a teaching assistant.

Mrs Leong says: "She allowed my son to wear a uniform. After we started the programme, we started an endowment fund to keep it going. The programme still runs today."

Together with several other parents and speech therapists, she also set up the Reach Me Project in 1997.

"We felt that the landscape for autism needed to change. We realised that time was needed for change, and it might not benefit our own children. But if we didn't do something, nothing will change."

It morphed into Autism Resource Centre (ARC) a few years later, offering assessment and diagnosis as well as information, training and outreach services. In 2004, ARC helped to establish Pathlight School, Singapore's first autism-focused school which now boasts more than 1,000 students.

Her eyes light up when she talks about her special son who qualified for John Hopkins Centre for Talented Youth when he was nine.

She has tales galore to tell of his primary school years at Anglo-Chinese School (Primary), like the time he lay on the floor and refused to sit for an exam because it did not start on time.

Keat Mun continued his secondary education in maths, science and art at NUS High School of Mathematics and Science.

Azusa Pacific University in Los Angeles was so impressed with his mathematics results that it offered him a scholarship but Keat Mun decided he liked art. He applied on his own to UniSA.

The Sunday Times e-mailed him to ask him why he did not pursue mathematics when he was so good at it. His reply, unedited, is: "I don't know why I would want to make a living crunching somebody else's numbers, not with the creative flair I have developed over the past several years."

He adds: "I want to design objects that look good, work well, and last for a long time, so we can shrug off whatever that is lobbed at us by the unscrupulous. Surely there is consensus for what counts as ugly or poor quality?"

It's not all smooth sailing, says Mrs Leong. She has been told that Keat Mun, who is in his third year, may struggle with his course because he does not talk. But she is determined to let him have a go.

The idea for Adelaide Harvests came about after an Australian friend, who once lived in Singapore, introduced her to beekeepers, cherry growers and other food producers. Mrs Leong's online business now sells a range of quality products ranging from artisanal olive oils to honeycombs and speciality vinegars.

Keat Mun, who has sold a few of his paintings, helps to design some of her labels and logos. Mrs Leong also employs her niece, who has Williams Syndrome - a developmental disorder - to stick labels on the products.

She says: "Whether Keat Mun will be a brilliant person, whether he can get a job, I don't know. I do know that he wants to learn."

And what does Keat Mun hope to be? "If anything, I would like to become a creative polymath in a world where the typical career sticks to a line of work. Fine arts, product, graphics, branding, comics, film, television; everything can be redesigned, nothing should be sacred."

WATCH THE VIDEO

Mrs Leong's journey of raising awareness for autism http://str.sg/4ehj