Gold Coast Detective Acting Superintendent Tim Trezise said evidence found at the Gold Coast unit suggested the five-year-old girl was asleep in bed as her mother and a 33-year-old man were stabbed to death at the weekend.
"In difficult circumstances like this, when we have a triple homicide and what we believe at this stage to be a suicide, it’s not easy to explain exactly why this happened," Detective Trezise said.
The body of Kyla's mother, Tania Simpson, 31, and the body of Antony Way were found dead in Ms Simpson's Robina unit around 8am yesterday.
The discovery sparked an abduction alert for Kyla, who police believe had been taken by her father Paul Anthony Rogers, 40, after the the murder.
Police have not yet officially named the man found dead with Simpson, citing the need to contact next of kin in New Zealand. But New Zealand media report he is Antony Way, formerly of Nelson.
The New Zealand Herald reported that Mr Way - who was known by many of his friends as 'Ant' - grew up in Nelson, attending St Joseph's Primary School and Nelson College.
He left New Zealand eight years ago and has been working in Australia as a renderer.
His family described him as an avid gym-goer and a keen rugby player.
"Ant was one of those charismatic guys with an X-factor who drew people to him,'' a family spokesman said.
"He had a sharp sense of humour and would give you the shirt off his back. He was generous, positive and had the most captivating smile.
The local area commander at Richmond in northern NSW, Superintendent Greg Martin, would not say whether Rogers left a note before dying in the car with his daughter.
"It's probably improper that I flush out all of the details of the investigation through the media when it's the coroner that should be finding all this out first," Supt Martin told reporters.
Bodies found by grandfather
The bodies of Mr Way and Ms Simpson were discovered by Kyla's maternal grandfather, who had arrived to take her to school. Acting regional crime co-ordinator Inspector Tim Trezise said police were 'gutted' at her death.
"It's just a waste, all these people dying, but particularly an innocent child like this one," he told a media conference at Gold Coast police headquarters today.
The child abduction alert for Kyla was not issued until about 3.15pm Monday but Insp Trezise said he did not believe it could have been issued any earlier.
He said police could not issue the alert until they had firm information and were also using mobile phone tracking to try to locate Mr Rogers and Kyla alive.
It's a bit early to speculate on the actual time of death but we would think that it wouldn't be long after the vehicle was first seen," Supt Martin said.
"It may not have really mattered the fact that we couldn't find the car when we first looked for it yesterday morning."
Kyla's mother and father reportedly planned to marry but broke up after an eight-year relationship.
Ms Simpson had moved to the Gold Coast to start a new life, but it is not known whether she was in a relationship with the man who was found dead.
The bodies of all four people involved in the tragedy will undergo autopsies in Brisbane to determine the exact causes of death.