Diamond Stone and Michael D’Angelo Archer, Stone’s children, are suing the drivers, a trucking company, and truck manufacturer Daimler Truck North America, according to court filings filed in Gwinnett County, Atlanta.

Stone allegedly survived the initial collision when the Mercedes-Benz Sprinter van transporting her, her group, and her bandmates overturned, according to the lawsuit. Five of the nine passengers were apparently rescued by onlookers, but Stone was still having difficulty getting out when the disaster happened again.

Stone was reportedly ejected on contact and pinned beneath the debris when a tractor-trailer transporting sugar crashed into the overturned van. She “consciously suffered,” according to the lawsuit, before passing away from her wounds. Her age was sixty-three.

The lawsuit also claims that the truck’s collision mitigation technology failed to stop the fatal collision and that the driver “was not paying proper attention to the roadway.”

At the time of the accident, Stone was on his way home from a show in Mobile, Alabama. In an emotional Facebook post, Diamond, her daughter, acknowledged her death with the words, “My mommy is gone.”

The Grammy-nominated singer first gained notoriety in 1979 as a member of the groundbreaking all-female hip-hop group The Sequence. Her 1999 debut album Black Diamond marked the beginning of a prosperous solo career. With classics like “More Than a Woman,” she became one of R&B’s most admired vocalists.

Fans and family are in mourning at her unexpected passing, and the lawsuit aims to hold people accountable for what her kids say was an avoidable tragedy.