A coroner's court heard that Kotomi Watanabe was asleep when her mother, Madam Maki Watanabe, 35, walked out of the Signature Park unit at about 3pm last Nov 6, leaving the door closed but not locked. She was afraid the locking sound would wake up her daughter.

While waiting at the lift lobby for the bus, Madam Watanabe heard a loud thud coming from the grass patch area.

She went to check and found Kotomi lying there. She picked her up and ran to the security post to seek help. An ambulance took the girl to National University Hospital where she was pronounced dead at about 5.10pm.

One of the two latent prints lifted from the ledge of the window glass panel in the living room matched Kotomi's fore finger's.

On Friday, State Coroner Earnest Lau recorded a verdict of misadventure on her death.