A Vancouver Island woman charged with drunk driving in the car crash that killed two of her children appeared in court Tuesday.

Clare Bekkers, 38, faces eight charges including impaired and dangerous driving causing death for the fatal Dec. 22, 2008 collision.

A former friend took the stand in B.C. Supreme Court on Tuesday, and testified that Bekkers had a cocaine problem. A toxicology report suggests there were traces of the drug in her system on the night of the crash.

Crown prosecutors are expected to wrap up their case against Bekkers on Friday.

"Counsel have worked hard to narrow down the issues. I think we're going to focus on what's really important. It's a factual case," Crown counsel Frank Dubenski said.

Bekkers's sons Lucas and Cooper were both killed when her Ford Escape veered out of control on Highway 1 south of Nanaimo. The SUV swerved into oncoming traffic and caused a seven-car pile-up.

Bekkers was also injured in the crash, as were her two other children. A total of nine people were sent to hospital.

Defence lawyers say they plan to argue that Bekkers was not impaired, and that the crash was caused by a combination of unfortunate circumstances, including poor winter driving conditions.