The sister of tragic Deborah Roberts has vowed to continue her fight to see more safety measures in place on the Sheppey Crossing.

Deborah Roberts, 42, and her eight-year-old son Marshall died on July 1 last year on the Sittingbourne-bound carriageway when their stationary car was hit by a van.

Sister Emma Tweed, speaking after the inquest, said she had “mixed emotions”, following the verdict of accidental death.

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She said: “Obviously it’s nice to be able to finally lay my sister and nephew to rest but we still will be pursuing more safety measures being put on the bridge and we will be pursuing further in court with Highways England.”

She called for the 50mph limit to be enforced by average speed cameras and matrix warning signs.

The inquest today heard the Roberts’s Renault Clio was stationary when it was hit by a Fiat Ducato being driven by Adam Chattaway, from Essex.

Betsy Danes, who gave evidence at the inquest, had been driving in a silver Peugeot 206 over the Sheppey Crossing after returning from work at Queenborough Primary.

She said she could remember a black Mini directly in front of her and what she initially described in a police statement as a white camper van behind.

She was travelling at about 68mph when she saw the car in front suddenly move to the outside lane without indicating – she later said she thought the driver would not have had time.

She then saw the Clio with no hazard lights on in the middle of the inside and described swerving into the other lane to avoid it before hearing a crash when she just cleared the Clio.

She said: “It was carnage. The van hit it very hard and there was debris flying everywhere. I was concentrating on getting somewhere safe to ring the ambulance.”

Guy Holland, an Asda delivery van driver who was going from the Island to the mainland, was directly behind the Fiat Ducato.

He said: “I looked up because I noticed the van’s brake lights for a couple of seconds but then they went off and I saw the van swerve to the lane nearest the central reservation as if it was trying to avoid something.”

"Obviously it’s nice to be able to finally lay my sister and nephew to rest but we still will be pursuing with more safety measures being put on the bridge and we will be pursuing further in court with Highways England" - sister of Deborah Roberts, Emma Tweed

A statement read out from Lucy Castle, who drove overtook Ms Roberts prior to the crash, said she saw the car moving “very slowly” down the slope with its hazard lights on and, after she passed, the car bonnet fully up.

Marshall’s six-year-old brother Archer, who was also in the car at the time of the crash but survived, said after the crash he saw his mother get out of the car to fix the bonnet but when she could not she went back inside to check the manual shortly before the car was hit.

Other statements from motorists said there was little traffic on the stretch of road at the time and a number said the Clio was stationary, just past the brow of the bridge and in the middle of the carriageway.

Some recalled having to swerve to avoid car which they said did not have hazards on.

It is not clear if or how the hazard lights were switched on and off again but the dashcam footage showed they were not on leading up to the crash.

The coroner later said the lights were off at the time of the crash but she was satisfied this was not a factor in the collision.

Mr Chattaway’s van was fitted with a dashcam and two trackers which recorded the speed and position of the vehicle and showed he was doing 70 mph at the time.

He said he cannot remember much about the moments leading up to the crash or the silver Peugeot in front of him and says he suffered shock after the crash which may have affected his memory.

He said he remembers checking his driver’s side wing mirror before seeing “a flash of red” and “yanking on the steering wheel as hard as I could”.

“It is a very great tragedy and a number of factors could have contributed to this collision” - Coroner Patricia Roberts

Senior investigator PC Terry Collins spoke at the inquest and said the Clio was about 200 metres past the brow of the bridge.

He said Mr Chattaway would have had 2.5 seconds in which to see the vehicle, perceive it was not moving and then respond.

He said had he been travelling at 50mph when the brakes were applied there still would have been an impact.

This was questioned by the legal representative of Ms Roberts’s family who said the impact would be less at the lower speed.

Tyre marks and data from the van’s accelerometer showed the brakes were applied only 6 to 12 metres away from the Clio, which had its handbrake on and was in neutral.

PC Collins said: “The collision was always going to happen with the Clio left in the position it was.”

The bridge has no hard shoulder and PC Collins said there may have been just enough space for the Clio to fit on a verge to the side of the road but if the bonnet had been up it would have prevented Ms Roberts from seeing where she was going.

A pathologist’s report said both Deborah and Marshall Roberts died after sustaining head injuries.

Granville Road, Sheerness, resident Ms Roberts, who wasn’t wearing a seatbelt, was thrown clear of the car and died at the scene.

Marshall, who was sleeping at the time but was wearing a seatbelt, was taken in an ambulance but was pronounced dead on route to Medway Maritime Hospital and is likely also to have died on the bridge.

In recording her findings, Coroner Patricia Roberts said: “It is a very great tragedy and a number of factors could have contributed to this collision.”

She said the location where Clio was when the crash happened, just over the brow and on a bend, would have impacted visibility of approaching vehicles.

The Peugeot travelling between the van and the stationary car would have restricted Mr Chattaway’s view ahead until Miss Danes moved into the outside lane, she said.

Lastly, she concluded the reaction period Mr Chattaway had to apply the brakes and swerve to avoid was also a factor.

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