Coroner Barry King is examining the circumstances surrounding the deaths of Heather Glendinning, 46, and her daughters Jane, 12, and Jessica Cuzens, 10, in their Port Denison home in December 2011.
In her opening address on Monday, counsel assisting the coroner Kate Ellson said the inquest would not examine how the trio died, but would determine whether anything could have prevented their deaths.
"The scene, and the manner in which the deceased died, can only be described as horrific, and it is not my intention, nor the purpose of this inquest, to examine them in any detail," Ms Ellson said.
The inquest heard Ms Glendinning met her ex-partner Harley Cuzens in 1996 and they had three children together, including Jessica and Jane, before separating in 2001 and becoming embroiled in a custody battle.
Ms Ellson said the pair were involved in "prolonged and complex legal proceedings, sullied by high levels of conflict".
During that time, Ms Glendinning exhibited obvious signs of increasing stress and medical professionals noted their concerns for her mental wellbeing, although there were no documented comprehensive mental health assessments.
"It appears Ms Glendinning did not seek help because she thought it would be used against her in her efforts to maintain contact with her children," Ms Ellson said.
The inquest heard that between 2007 and 2011, there were several opportunities where further or different mental health care options could have been explored through the Family Court, Geraldton Mental
Health Services, and friends and family.
"Bearing in mind it was for Ms Glendinning alone to choose to co-operate and be truthful with people, this inquest will attempt to explore whether any intervention by medical services may have changed the outcome for her and her children," Ms Ellson said.
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