Heartbroken mum of drowned boy reveals precious last days together.

When Lauren Hilton closed her eyes last night, it wasn’t sleep that came. Instead she was haunted by horrific visions of her child’s last moments, trapped inside a rapidly sinking car.

Police divers recovered the body of four-year-old Bentley Hilton from the depths of Hawesbury River at Lower Portland in New South Wales on Sunday, several hours after his grandfather’s ute slid off a boat ramp with him strapped inside.

“I tried to close my eyes last night and all I could see was him,” Lauren told Seven News, “wanting to get out, yelling out for help.”

Lauren, who is separated from Bentley’s father, told The Daily Telegraph that her son was a “happy” and “bright little boy”.

“It was Mother’s Day the last night I saw him,” she said, “and I spoke to him on Saturday night and he was happy telling me about everything he was doing. We were laughing and giggling.”

Channel 7

Bentley's grandfather had left him in the passenger seat of a Ford Falcon ute at around 10:45am on Sunday, as he untied a small dingy from the roof.

Tragically, the vehicle began to roll backwards and ultimately sunk into the deep, murky water.

The little boy's father and grandfather spent 25 minutes desperately diving in search of the boy, before emergency services arrived and established a rescue operation.

The vehicle was recovered four hours later, washed 20 metres downstream. Bentley was pronounced dead at the scene.

In the days since, members of the little boy's family have spoken about their grief, including his step-aunt who posted the following message to Facebook.

"Everyone keeps tell me that you are gone but you can't be none of this can be true your to young to leave us you have your hole (sic) life ahead of you, please just tell me they are all lying and come back to me, I love you so much Bentley more then you could ever imagine. So blessed to be your Aunty. I miss you so much please just come back. Your my angel now I hope your resting easy up there baby."