In 2011, her twin sister Tan Suxuan died suddenly, of a mystery illness her parents still struggle to explain.
On Saturday, part-time student Tan Sumiao, aged 23, succumbed after undergoing 11 operations in 45 days in a battle with a rare virus.
As the heart-rate monitors beside her bed flatlined on Saturday evening, loud sobs erupted from more than 20 friends and relatives who had gathered at her bedside to say their final goodbyes.
Even a doctor broke down in tears, said Miss Tan's father, Tan Sew Poh, 64.
Her death certificate says Miss Tan died of cardiorespiratory failure - the failure of the heart and lungs to function - pending further investigation.
But to her father, her death, while coming as a huge shock, was a merciful alternative to the likelihood of a life fraught with suffering.
Said Mr Tan in Mandarin: "The doctor had told me that even if she had survived this, her condition meant that she would have had many complications.
"Now she does not have to worry about pain, or of being bedridden. Short pain is better than lengthy suffering, and she went peacefully."
Mr Tan spoke to The New Paper at his daughter's wake on Sunday.
He explained that her illness had started with a mild fever, which did not go away after visits to their family doctor for almost two weeks.
On July 29, she was warded at Alexandra Hospital with fever, and was transferred to National University Hospital the next evening when she had breathing problems.
There, she was sent for surgery and was transferred to the intensive care unit.
Said a close friend of three years, Alvin Lee, 22: "Before she was taken to the hospital, she told me she felt very tired. She had a dry cough, but she didn't seem to think it was anything serious."
But Miss Tan's parents feared the worst, having lost their younger daughter three years earlier.
Said Mr Tan: "My wife and I were mentally prepared for this after she was warded."
He and his wife, See Beng Hwa, 63, visited their daughter daily, despite their jobs as a part-time bookkeeper and clerk, respectively.
Said Mr Tan: "We went every day to look after her and give her massages."
He said that Miss Tan was conscious but could not speak, and was only able to open her eyes and move her fingers.
Then the call came on Saturday evening, informing the Tans to be at their daughter's bedside as her condition was deteriorating.
It was heartbreak all over again for the Tans who, in 2011, had to endure two weeks of their other daughter's coma before she died.
Mr Tan said that Miss Tan Sumiao had been deeply affected by the death of her identical twin.
"I had told her to be strong, there's no point harping over what is gone.
"But I did not expect her to go too."
When asked about his plans, now that his children are gone, Mr Tan shook his head and replied: "What can I do?"
Miss Tan's medical bills came to about S$40,000, which was much more than what he had to pay for his younger daughter's treatment, he said.
The medical bills have wiped out the couple's savings. They earn a combined income of about S$1,700 a month.
He said: "I used to tell Sumiao that when both papa and mama are gone, there's no need to worry. She can rent out the flat and live with relatives."
Now, he might have to heed his own advice and rely on help from relatives and friends.
"There's not much (savings) left. Maybe a few thousand, that's all," said Mr Tan.
Miss Tan's body will be cremated at Mandai Crematorium tomorrow.
This article by The New Paper was published in MyPaper , a free, bilingual newspaper published by Singapore Press Holdings.
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