A 3-year-old child was found bleeding profusely at the foot of Blk 332, Ang Mo Kio Avenue 1 in the early hours of Tuesday morning (Feb 18).
The boy was believed to have fallen from his home on the seventh storey while looking for his grandparents after waking up.
He was pronounced dead at the scene by a paramedic.
A hairdresser chanced upon the scene as the body was being taken away at 7am.
Speaking to a reporter from Lianhe Wanbao, the 22-year-old recounted an exchange with a woman she met at the market.
"She passed by the block earlier and saw a child, about three to four years old, lying on the ground and bleeding profusely from the head."
Another resident told the Chinese daily: "Before the incident occurred, I heard the sound of a child crying from their unit".
According to the paper, the boy's grandmother had gone out at around 5.30am to work at a nearby coffee shop. She returned home at 7am to take him to his childcare centre and realised that he was missing.
Looking out the kitchen window, she noticed a crowd gathering around her grandson's body. When she rushed downstairs, he had already stopped breathing.
The boy lived with his grandparents in the unit and was previously under the care of a domestic helper. When he started attending school, his grandmother became his main caretaker.
The police said they were alerted to a case of unnatural death at 6.38 am. Investigations are ongoing.