The infant was flown to Starship children's hospital with critical injuries but died in hospital on Monday afternoon.
The driver of a van that struck a runaway stroller, Sudhir Saksena, told the Herald how it was a nightmare that he couldn't shake from his mind.
He said the stroller rolled down the hill in front of his car "out of nowhere".
"The pram went flying down the hill right in front of me. I slammed on the brakes but it was too late," he recalled, shaken by the ordeal.
"I didn't see it coming ... I slammed on the brakes but it was too late."
The driver had since returned to the scene with candles to light in memory of the child. He revealed he sat with his wife and wept.
Police say they were continuing to investigate the incident and providing the family with support during this extremely difficult time.
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