A young boy killed alongside four other teenagers in the fatal Buxton crash is being remembered as a "happy and humble" kid and a father's "best friend".

Fifteen-year-old Antonio Desisto was one of five teenagers killed in a horror ute crash in Buxton, south of Sydney, on Tuesday night.

"He literally never left my side," his father Exaven White said.

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"I didn't have many friends, I do have a couple of best mates but my son was my best friend, my mate, we did everything together."

But now, the harsh reality that White has lost his son is sinking in.

"I have to see whatever is left of him. I don't even want to go see him but I need to see him."

White spoke outside court after the driver of the car, Tyrell Edwards, was refused bail after being charged with five counts of dangerous driving occasioning death.

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Four other teenagers, Summer Williams, 14, Lily van de Putte, 15, Tyrese Bechard, 16, and another 14-year-old girl who cannot be named for legal reasons, were killed in the crash.

Family and friends have left growing floral tributes and memorials at the site of the crash.