He said Dylan's death was "a complete tragedy".
"Infant driveway deaths are by no means unusual. Dylan's death is, however, unusual in that almost always infants are killed in driveways when a vehicle is reversed."
New Zealand has among the worst child driveway death rates in the world, with an average of about five children killed each year, mostly by reversing vehicles.
Parents Raymond and Janet Harre had been packing at their home on a farm in Whangamomona, Taranaki, for the family's move to Piopio in the King Country.
The tragedy happened when their long-time friend and neighbour Walter Pease went to move his ute and trailer at the request of Mr Harre's mother, whose car was blocked in.
He drove forward about 5m before looking into his rear view mirror, intending to reverse.
That was when he saw something he could not identify, followed by Janet Harre running towards the trailer.
Mr Pease got out of the ute to find Mrs Harre holding Dylan.
She gave evidence that Dylan was an active baby who was about a month from starting to walk.
Dylan was thought to be in the garage at the time, but Mrs Harre said he must have crawled under the trailer or pulled himself onto it - an assessment Coroner Scott agreed with.
He found the only way Mr Pease could have avoided striking Dylan was if the child was under close supervision, or if Mr Pease had walked around the ute and trailer, checking carefully before driving off.
Coroner Scott urged everyone involved not to "beat up on themselves" any more than they had already done, saying there was nothing to be gained from that.
"Nevertheless Dylan's sad and tragic death is a terrible reminder to us all of the need for great caution when supervising children and when moving motor vehicles - especially when young children are known to be in the general vicinity even if they are thought to be elsewhere."
Driveway safety advocate Clive Matthew-Wilson, editor of car review website dogandlemon.com, said it was a very unusual driveway death, given the vast majority were caused by reversing vehicles.
"But if the vehicle was driven forward, then it literally is just one of those freak accidents that happen. And of course it's a constant reminder to check the whereabouts of children before you move a vehicle on a driveway."
AA motoring affairs general manager Mike Noon said driveway deaths were incredibly upsetting.
"They are just tragedies, really - they're our youngest and most vulnerable. Those involved are terribly affected by what has occurred, through inattention or circumstances."
He said drivers needed to check all around vehicles before moving them.
