Charges againts a Cairns mother who has been arrested over the suspected murders of seven of her children, along with her niece, appeared increasingly likely on Saturday afternoon.

But investigators said charges against Mersane Warria would most likely not be laid until at least Sunday.

Ms Warria, 37, was the biological mother of nine children, investigators have revealed.

She was placed under arrest on Friday night as she was recovering from knife wounds in Cairns Hospital.

Detective Inspector Bruno Asnicar said family members were able to positively identify the eight children – four girls and four boys – on Saturday afternoon.

Ms Warria's daughters were aged two, 11 and 12, her niece 14.

Her sons were aged five, six, eight and nine.

"Every minute, we have a better understanding of what went on in the house," Inspector Asnicar said.

"And I can assure you that by the time this investigation is completed, we will understand every single movement, everything that happened, in that house."

One of Ms Warria's two older sons, believed to be aged about 20, discovered his siblings' bodies in the Murray Street, Manoora, house on Friday morning and raised the alarm.

He also found his injured mother, who is understood to have suffered stab wounds to her neck and chest.

Inspector Asnicar would not comment on whether those wounds were self-inflicted.

But as the investigation went on, with Ms Warria under arrest on suspicion of murder, charges appeared increasingly likely.

"Charges are being considered, of course, and investigations are continuing, obviously in that direction," he said.

"At this stage, we haven't [laid] any charges and as soon as we do, we'll let you know."

Inspector Asnicar said Ms Warria's seven slain children had, between them, five fathers.

When the parents of Ms Warria's niece were also considered, there was a total of eight parents – including Ms Warria – directly impacted by Friday's events.

"Even under these horrific circumstances and the trauma they've been through, the support that the family's been giving us in this investigation has been outstanding," Inspector Asnicar said.

"It's been because of them this (identification) process has been able to be done in a really calm, easy and least intrusive way as possible."

Inspector Asnicar said he expected the Murray Street home to remain a crime scene for another two or three days while forensic officers examined evidence.