The girl was sexually abused by her uncle since she was just five.
Her sister, who is a year younger, witnessed one of the attacks.
But when the girls tried to tell their grandmother about what happened, she scolded them for making things up and the sisters kept the abuse a secret for seven years.
The younger girl spoke up only last year, telling a teacher about the abuse to protect a third sibling.
Their uncle, a 29-year-old former deliveryman, was yesterday sentenced to 6½ years' jail in the High Court.
He had earlier pleaded guilty to three charges - two of carnal intercourse, and one of committing an indecent act with a child. Four other similar charges were taken into consideration during sentencing.
We cannot name any of the people involved because of a gag order to protect the victim's identity.
At the time of the attacks between 2006 and 2007, the girls lived with their grandmother and uncle in a flat in central Singapore because their mother worked shifts.
Their uncle had just finished serving his national service and was unemployed, so he helped look after the girls while their grandmother and mother were at work.
As part of their routine, both girls would take an afternoon nap when they got home from school. The older girl would pat her sister to sleep before tucking herself in.
One afternoon between June and December 2006, the victim had put her younger sister to bed when their uncle called her into his room.
He took off his shorts and asked the victim to massage his hips, legs and private parts.
The girl did not know what her uncle meant, so he took her hand and placed it on his private parts and made her masturbate him.
He stopped only when the girl said her hand was painful.
A week after the incident, the uncle asked the girl into his room under similar circumstances and made her do the same thing.
This time, he also instructed her to perform fellatio on him, using both his hands to help her perform the act.
Some time in 2007, the uncle called the older girl into his room again while her younger sister was sleeping in the living room. This time, she knew what she had to do.
As she was performing fellatio on him, she saw her sister looking at them from the living room through a crack in the door, which had been left ajar.
After the abuse, the victim went to the living room where she watched television with her sister, pretending nothing had happened. Months later, when the sisters talked about what happened, they decided to tell their grandmother about it the next day.
But the elderly woman did not believe them and scolded them for making such allegations.
As a result, they decided to treat the abuse as a secret, thinking that they were children and no one would believe them.
The offences came to light in July last year when the younger girl told a teacher that she did not want to go to school.
Their mother had given birth to another girl, who was three then, and the child was being looked after by their grandmother in the same flat where the attacks happened.
The then 12-year-old said she was worried about what her uncle might do to her younger sibling and spoke of what had happened to her older sister seven years earlier.
Their uncle was arrested shortly after.
The man's defence lawyer, Mr Ismail Ismail, told the court that his client has decided to contribute to society by joining the Community Centre as a member of the Residents' Committee. Mr Ismail is representing the uncle for free.
He said the victim's mother has forgiven her brother for what happened.
Victim suffered flashbacks for years
According to a report from the Child Guidance Clinic, the victim had flashbacks of the attacks until she was in Primary 5, nearly six years later.
She also felt upset and would "slash her left forearm during the unbearable moments".
Furthermore, she had passive suicidal thoughts because of her family's problems, experiencing periodic episodes of "low mood".
Psychiatrists and psychologists The New Paper spoke to said these are signs of post-traumatic stress disorder and it is something the girl will constantly battle unless properly counselled.
Dr Carol Balhetchet, senior director for youth services at the Singapore Children's Society, said victims of sexual attacks tend to feel betrayed, unsafe, and even guilty.
"(The girls) went to their grandmother looking for help, but she 'betrayed' them, so this may even lead to feelings of abandonment," Dr Balhetchet said.
There is also a concern that the victim may become hypersexualised, or express sexually promiscuous behaviour, said Dr Thomas Lee, a psychiatrist in private practice.
This is a manifestation of the self-harm that victims would tend to inflict on themselves.
Dr Lee said: "Victims don't know how to manage their inner feelings so feeling physical pain would help them to release their emotions."
But it is not just the victim who suffers from trauma.
Even the younger sister, who witnessed the attack, might be affected, said Dr Lim Boon Leng of the Dr BL Lim Centre for Psychological Wellness.
"If they are very close (as in this case), the younger sister would need to be assessed and also counselled because she is likely to have similar problems," he said.
This article was first published on September 17, 2015.
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