Gun laws may be tightened to consider a person's mental health depending on the outcome of an inquest, amid reports the grandfather at the centre of the Osmington murders-suicide began taking antidepressants weeks before the massacre.

Peter Miles, 61, his 58-year-old wife Cynda, their daughter Katrina, 35, and her four children - daughter Taye, 13, and sons Rylan, 12, Arye, 10, and Kadyn, eight - were found dead at Forever Dreaming Farm on May 11.

West Australian Premier Mark McGowan said he did not want to "jump to conclusions" about Mr Miles' mental health or what happened at the hobby farm before anl inquest could be held into the tragedy.

Asked whether a person's mental health should be a factor in considering their gun licence, Mr McGowan said he supported extremely tight gun laws.

"It's an area which is difficult because you don't want to put people off seeking attention," he told reporters on Sunday.

"If someone knows if they seek attention and support they're going to lose other aspects of their life they might like, they may not seek the attention or support, so it's a tricky area.

"The coroner will no doubt look at all these things. The advice the coroner provides us will be very persuasive in what steps we take.

"Whatever we do, I think it has to be coordinated nationally."

But Mr McGowan said he did not want to pre-empt the coroner's findings.

Readers seeking support and information about depression and suicide prevention can contact Lifeline on 13 11 14.

Suicide Call Back Service 1300 659 467.