It was the middle of winter, 2018, when a man named Bruce Wilson heard what he describes as "an almighty bang".
Just past 5pm on a Thursday, West Pennant Hills was normally quiet and still. Located about 20 kilometres from Sydney's central business district, the suburb is known for its wide, leafy streets, full of young families.
But on July 5, the neighbourhood felt different.
Wilson approached the house next door, and watched as John Edwards, 67, half skipped down the stairs.
He thought to himself, "I've got to concentrate on his features, and his height... because I think he has shot the children."
Wilson eventually made his way to the neighbour's front door and says he stood there for a while. "It just felt demonic," he told an inquest earlier this month. "So bad, such an eerie feeling of standing there."
His instincts would prove correct.
That evening, police entered the three-bedroom house on Hull Road, and discovered the bodies of 13-year-old Jennifer Edwards and 15-year-old Jack Edwards. They had been shot with a handgun police have only described as "powerful".