Police are investigating the possible murder-suicide of a young couple found dead inside their Queensland home.

A 27-year-old woman and 30-year-old man were found dead inside their Eagleby home in Brisbane's south about 1.15pm on Monday.

The couple's three daughters, now orphaned, were not believed to be in the home at the time of their parents' deaths.

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Three young children have been left orphaned after their parents were found dead inside their home (pictured are toys left outside the home)

Neighbours on Francoise Street said the children, understood to be 15 months, four and five-years-old, were not living with their parents in the lead up to their death.

The mother voluntarily gave her kids up for about a month in lead up to the suspected murder-suicide because she 'needed to get her head clear', a neighbour told the Courier Mail.

A close friend said she saw the mother on Thursday, just four days before she was discovered dead.

She said the woman borrowed clothes to wear before going out to a Brisbane pub for karaoke.

'She seemed okay,' she said.

The couple had been living in the house (pictured) since October, but their children were not living with them

Police tape is seen outside a house in which two bodies were found in Eagleby, south of Brisbane on Tuesday

The friend said that was the last she saw of the young mother before learning of her death on Monday.

The friend said her son often played with the couple's daughters but had not seem them for a while.

Simone Whye, another neighbour on Francoise Street, said the couple's deaths came as a shock.

'It's just completely uprooted the street… I didn't think they'd do that, and having left three girls behind,' she said.

Neighbours said the couple had not been seen since Thursday, and their children - aged five, four and 15-months-old, had not been living at the home (pictured)

Simone Whye, a neighbour and 18-year resident of the street, said the couple's death seemed 'out of sorts' (pictured are police outside the house where the bodies were found)

Ms Whye, an 18-year resident of the street, said the couple had been living in the house since October.

While she didn't know them well, she said 'they were very quiet, very friendly people'.

A post-mortem was undertaken on Tuesday to determine the couple's causes of death.

Queensland Police believed the couple's bodies were in the house for about two days before they were discovered.

The police said the bodies showed no signs of injury when they were found.

Children's toys could be seen sitting in the backyard of the house, which is still cordoned-off with police tape.