SINGAPORE - Younger sisters are typically doted on and cared for by their protective older brothers.
But for Miss Lim Geok Shan, the youngest of three siblings, the roles are reversed.
She was only about nine years old when, in 2004, her oldest brother, Ambrose, was diagnosed with a rare inherited eye condition.
Three years later, her second brother, Aloysius, was also afflicted with the same condition.
Both brothers were about 13 when they were diagnosed. They had previously had perfect eyesight.
The eye condition, called Leber Hereditary Optic Neuropathy, affects the central vision.
And spectacles cannot help.
The side vision, however, is not affected - the brothers can actually see more clearly from the sides.
When they watch football on TV, they sit with their faces mere inches away from the 32-inch screen, effectively blocking everyone else.
Geok Shan has not been discovered to have the defective gene.
Dr Clement Tan, a senior consultant with the National University Hospital Eye Surgery Centre, said males are more frequently affected than females, though the reason is not known.
But Geok Shan wishes she could "suffer" in place of her brothers.
The 18-year-old, who just completed her A levels, said: "When they were diagnosed, I felt really bad. I kept asking and blaming God, 'Why them?'
"I asked why I wasn't the one to suffer instead."
Because simple tasks like reading, writing and boarding the correct bus have become mammoth undertakings for her brothers, Geok Shan takes it upon herself to help them.
She said: "I had to adapt and learn their needs."
"But now, our roles have changed. If I don't help them out, who will?"
Dr Tan said there is no surgery or well-proven treatment for the condition.
It is so rare that in Europe, it affects about one in 30,000 to one in 50,000.
Dr Tan said there are no local figures.
He added: "Once low vision has set in, treatment revolves around providing assistive devices that essentially magnify what the patient can see as well as mobility training."
Reading and writing takes great patience and determination.
The brothers would pore over their textbooks, reading word by word, often taking hours at end.
And late into the night, when work was still aplenty, Geok Shan would help by reading it aloud to her brothers.
Their special tools include a pocket-sized magnifying glass, a hand-held electronic magnifier for classroom purposes and a bulkier desktop magnifier for home and examinations use.
But these do not come cheap. A desktop magnifier costs $5,000 to $6,000 and each brother has their own.
Fortunately, the family receives huge subsidies.
Aloysius, 19, completed his A levels at Millennia Institute (MI) last year.
Studying and preparing for the examinations required twice the time and effort compared to his peers, he said.
But his efforts paid off.
The New Paper reported on his stellar results - three As in H1 Chinese, H1 Mathematics and H2 Accounting - earlier this month.
But his brother did not have it as easy.
Ambrose, 22, who also went to MI, took his A levels three times.
With each attempt, his results improved slightly.
From failing it on his first try, he eventually achieved a D in his General Paper.
After getting his results last year, he started looking for a part-time job in cleaning.
"I wanted to work so I could spend my time more meaningfully. I thought my condition wouldn't enable me to do anything else," he said.
But he had difficulties getting hired.
Desperate, he approached Dr Vivian Balakrishnan, Minister for the Environment and Water Resources, at a meet-the-people session in Bukit Panjang last June.
At a meeting with the Lim family at a cafe in Bukit Panjang Plaza earlier this month, Dr Balakrishnan said he was shocked by Ambrose's request for a cleaning job.
Said Dr Balakrishnan: "I told him that with his grades, he could definitely get a better job."
With the minister's help, Ambrose has been working as an administrative assistant at the Singapore Environment Council (SEC) for the past nine months.
At work, his computer monitor, at 23 inches, is the largest in the office.
Mr Damon Yong, director of partnerships development at SEC, had praises for his work.
"He is extremely intelligent and meticulous. He's really good with numbers and data analysis and we let him build on these strengths."
He added: "The guidance and treatment we give Ambrose is the same as anybody else."
And that's exactly what his father, who wanted to be known only as Mr Lim, wants.
The 52-year-old technician said: "I don't like telling other people about my sons' condition. Why should we tell everyone and allow them to be judged?
"I want, most of all, for my sons to be treated normally."
The brothers have difficulties when travelling as they are unable to see the bus numbers clearly.
They were encouraged by close friends to use a white walking cane which blind people use, but they refused to do so.
Said Ambrose: "If I were to use it, people would give up their seats for me (on public transport). But I don't want that. I don't want to be treated like someone with special needs."
"I felt like my whole world was collapsing. I thought, 'How could it be possible if this inherited condition isn't in my family's genes?'"
He later found out that in his wife's extended family, two others suffer LHON from the eye condition.
Dr Tan said the eye condition is inherited through a mother who is a carrier of the abnormal gene - two others in Mr Lim's wife's extended family suffer from it.
Ambrose lost his central vision completely within about six months of being diagnosed.
Mr Lim was prepared for the worst when Aloysius first noticed a deterioration in the vision of his left eye in Primary 6.
He was relieved to find out that Geok Shan did not have a high chance of LHON getting the eye condition.
On his daughter's selflessness and help to her brothers, Mr Lim said: "As parents, we can only provide for the boys' basic needs. That's where she comes in, helping them with their daily and emotional needs. And she's never complained.
"Without her, it really wouldn't be as easy."
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