Housewife Chandralega Sandragesan was about to head home from Choa Chu Kang Polyclinic last Friday when a taxi struck her youngest son and drove off.
The impact flung 11-year-old Thivakar Alivaran about 2 to 3m across the road. The primary school student had gone to the other side of the road to try and flag a cab, and was crossing back when the accident happened.
"I thought he was dead," said Madam Chandralega, 43. "I heard a loud bang and saw my son flying diagonally across the road."
With her one-month-old granddaughter in her arms, she ran to Thivakar's motionless body and shouted at him to wake up.
"Thankfully, he did," she said.
Thivakar's sister, Mrs Nagarani Mathyalakan, 19, ran to the Prime taxi and beat on the driver's window, shouting at him to get out of the car.
Mrs Nagarani, who had gone to the polyclinic with her family for her daughter's medical appointment, said: "I wanted him to take responsibility for his actions."
But she said the driver, who had a passenger, wound down his window, took a peek at her brother and drove off.
The family boarded another taxi and rushed to KK Hospital, where Thivakar has been hospitalised since Friday for a hairline fracture on his right ankle.
Madam Chandralega said she was so badly frightened that she fainted on the way.
Thivakar is expected to be discharged today. When the Straits Times visited him at the hospital yesterday, he looked tired and complained of a bump at the back of his head, as well as numbness and pain in his left thigh and spine.
Madam Chandralega said: "He cries whenever I leave his side, so I am here from 10am to 1.30am for the past three days taking care of my son and my granddaughter."
Since Friday, Thivakar said he has problems falling asleep and has been unable to forget the harrowing episode. He also said he is afraid to take taxis and does not want to visit the polyclinic anymore.
"We are still trying to figure out how to get him home (without a taxi) after he is discharged," said his brother, Mr Nagarajan Mathyalakan, 21, a tattoo artist.
A spokesman for Prime Taxi said the company is investigating the case, but declined to comment further.
Police said investigations are ongoing.