While it is not a crime for parents to leave their child alone for a short period, experts warn against doing this.
"Even if parents don't intend to neglect their child by leaving them alone, you just never know," said Ms Sujeeta Menon, head of centre at Residence @ St. George's, a girls' hostel.
And safety precautions may not work.
"Within seconds, a three-year-old can do all sorts of things as they see the world with curiosity," said Dr Carol Balhetchet, senior director for youth services at the Singapore Children's Society.
There is no one-size-fits-all solution to when a child can be left alone.
Said Ms Menon: "Consider factors like whether the child has started to go to school, takes the bus on his own and if he recognises the dangers of talking to strangers."
Dr Balhetchet said: "Giving children verbal instructions may not work at that age as they'll forget within minutes. I would consider leaving them home with fixed instructions only at the age of six and above".
They were commenting on Thursday's incident at Block 371, Jurong East Street 32, where a toddler who had been left alone was rescued after getting her head stuck between the railings in her home.
Mr Ang Wei Neng, MP for Jurong GRC, said that his representatives visited the family yesterday and offered to install grilles in their flat for free.
This is part of an initiative to help needy families get basic equipment like rice cookers from the Jurong Central Citizens' Consultative Committee's Project Helping Hand fund.
"While grilles have been installed in many units in Blocks 373 and 374, Block 371 is still a work in progress," Mr Ang said.
Lawyer Luke Lee said the police typically investigate a case where an injury or death has occurred as one of negligence. In this case, since the toddler was successfully rescued and unharmed, her parents could be let off with a stern warning.
Investigators will consider the gravity of the danger the child was put in, compared with what was needed to be done to repair that danger, he said.
Another lawyer, Mr Rajan Supramaniam, director at Hilborne Law LLC, said prosecutors have to assess if the parent has taken all reasonable steps to ensure the safety of the child.
A seven-year-old boy fell 11 storeys from his flat to his death.
Chan Wei Tao is believed to have panicked after he woke up from an afternoon nap and found himself alone at home. He reportedly wandered to a chair at the kitchen window, climbed on it and fell out of the window.
Marson Heng Jing Quan died of head injuries after he fell from his three-room flat at Tampines Street 42.
The five-year-old kindergarten pupil, who was asleep, was left alone at home when his father left for work at around 8.15am.
A woman found her four-year-old granddaughter lying dead at the bottom of her Simei block after returning from a trip to buy coffee. The girl was asleep, the window grilles were unlocked and the maid was not around, said a neighbour.
This article was first published on April 25, 2015.
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