Broken spectacles, a purse and a wallet were among the few recovered possessions belonging to Mr Logan and his parents Patricia and Donald Logan after a drug-affected truck driver slewed across the highway and slammed into their car, killing them instantly.

But Patricia and Donald's surviving son, Gary Logan, told the truck driver's sentencing hearing on Friday that one item stood out in the painfully small collection.

"There was nothing of any consequence ... except the ring," Mr Logan told the Downing Centre District Court.

"My father gave it to mother a few months before ... on their 60th wedding  anniversary.

"It was then that the nightmares began."

In a powerful victim impact statement, Mr Logan spoke of waiting for his family's expected arrival on the afternoon of January 24, 2012. as they drove back from visiting their baby granddaughter and great-granddaughter in Canberra.

"By 1pm we were worried and wondered if they were changing their plans," he said.

"By 3pm we were calling and sending text messages.

"At 5pm I swiped my phone and the Sydney Morning Herald [website] coincidentally appeared and the photo of my brother's car, crushed, appeared as the top headline ... I knew it was them."

The accident was, in Mr Logan's words "senseless and utterly avoidable".

The Logans were driving along the Hume Highway near Menangle when a red B-double being driven by Vincent Samuel George in the opposite direction veered across a 15-metre grass median strip, crushing the sedan.

Mr George was later found to be under the influence of a large dose of methadone, which he had obtained illegally, and had been driving for the past 22 hours with a break of only four-and-a-half hours.

He was later convicted of three counts of negligent driving occasioning death, drugs charges, and charges relation to improper use of his vehicle.

"Death is inevitable in this world, but for my parents and my brother to be killed so senselessly and so violently is too shocking and too reprehensible to contemplate," Mr Logan said, crying.

"They were law-abiding, peace-loving and kind, and they did not deserve to die in such a horrific way."

The court heard that 1300 people turned up to the trio's memorial service, many of them Jehovah's Witnesses; the elderly couple had devoted much of their lives to the faith.

After Mr Logan read his statement, George made a brief statement to the court apologising to the Logan family.

"If there was some way I could have gone over that bridge myself, I would have," said the former truck driver, who has been assaulted in jail by a fellow inmate.

"I can't tell you how sorry I am. I never meant for anyone to get hurt.

"You don't realise these things are going to happen when you're pushing and working ... trying to get ahead in life."

But the sentencing judge, Stephen Hanley, expressed doubt about the offender's apparent remorse.

He pointed to the fact that during the trial, George had attempted to blame a young P-plater who was ahead of him on the road as evidence that he "still hasn't come to terms with what he's done".

The judge also questioned why the company that employed George and reportedly allowed him to keep driving, despite his well-known habit of refusing to stop for the required rest periods.

"Surely they must have known from the regular contract they had with this man what his sleep records were and what his driving record was," Judge Hanley said.

George will return to court on September 12 for sentencing.