The accident happened last July in Mechelen at a junction where the traffic lights were out of action. The driver, known only as EV, ran into the car driven by Danny Vermeiren, travelling with his wife and four children. The impact sent the Vermeirens’ car rolling onto its roof, killing nine-year-old Thibo and one-year-old Ina.

According to accident experts, all of the children were fastened with seat belts. But the closure of the baby’s child-seat was internally damaged and gave way on impact.

EV admits causing the accident by ignoring the rules of priority at the junction but is claiming damages from the family for the mental and physical suffering the crash has caused him. If the children had been better fastened in by their parents, his action claims, he might not have their deaths on his conscience. Thibo’s death, too, is being investigated. The booster-seat on which he was sitting is for children up to 32 kilograms, said EV’s lawyer, Gert Beulens. “We now want to find out if the boy wasn’t heavier than that.”

Danny Vermeiren, meanwhile, described the legal action as “a knife in our hearts. This document is accusing us literally of causing our children’s deaths.”