Extra charge for daughter death crash mum

A 47-year-old woman has been charged with a drink driving offence over a car crash in Perth's northern suburbs that killed her teenage daughter.

Janet Louise Kirby has already been charged with four offences including dangerous driving occasioning death over the crash in Merriwa on the night of March 14.

There were seven occupants in the jeep, including five children, when it left the road and rolled over on Marmion Ave.

Lois Kirby, 15, was thrown from the vehicle and died from her injuries while a 20-year-old woman suffered serious injuries to her left arm, which required surgery.

On Wednesday, police said the driver had also been charged with driving with a blood alcohol content in excess of 0.08 per cent.

She is due to appear in the Joondalup Magistrates Court on May 25.

When Ms Kirby first faced court hours after her daughter's death, a medical assessment was ordered as she was sobbing uncontrollably.