A coroner is urging tighter checks on vehicles which are written off, repaired and re-registered after a child's death in such a car.
Sadie McGrady, six, died in July 2012 when her mother's Vauxhall Corsa was hit by another vehicle in Flintshire.
An inquest heard the family's car had been repaired after being written off by insurers in 2008.
Coroner John Gittins said he understood no-one was to be prosecuted and reached a conclusion of accidental death.
Mr Gittins, the North East Wales senior coroner, said he would be raising concerns with the Association of British Insurers, the DVLA, the Vehicle Operating Standards Authority (VOSA) and other bodies.
He said he wanted to highlight the way the vehicle had been written off but four years later was being driven "legally and legitimately" when the integrity of the vehicle had been compromised.
The inquest was told Sadie from Mostyn, Flintshire, was sitting behind her mother Catherine Barlow, the driver, when the collision happened on the nearby A548 coast road.
Mark Buckley from Ashton under Lyme told the hearing he was overtaking vehicles on the eastbound dual carriageway at about 60 to 65mph when Miss Barlow's car suddenly appeared in front of him, crossing over the carriageway from a garage on his left.
Miss Barlow's car was shunted into the opposite carriageway and when an off-duty nurse went to help the occupants, Miss Barlow said: "I'm so sorry. What have I done?"
Sadie, who suffered head injuries, died at Glan Clwyd hospital, Bodelwyddan, Denbighshire. Her cousin and sister were also sitting in the back seat.
When interviewed, Miss Barlow said she had waited for one car to pass, seen Mr Buckley's car approaching about 200 metres (656ft) away and thought she had enough time to cross to the central reservation.
The police vehicle examiner said the integrity of Miss Barlow's car had been compromised by the poor repair, resulting in the door pillar and panel being less able to withstand a sideways impact.
Collision investigator Gordon Saynor said the only checks carried out after "write-offs" had been repaired were routine annual MoTs which would be unlikely to reveal hidden substandard work.
"The intrusion into the passenger compartment may have been less had the repair been done to industry standard," the coroner told the inquest at Ruthin, Denbighshire.
Sadie was a pupil at Ysgol Bryn Pennant, Mostyn and her father Paul McGrady said she loved singing and dancing.
"Her death has left a massive hole in our lives which will never be filled," he said.