KEY POINTS:
SYDNEY - The mother of two young children found dead in a Sydney home was discovered lying beside their bodies, tucked up in a bed, a neighbour says.
The 29-year-old mother was today in hospital under police guard, with injuries to her wrists, following yesterday's horrific discovery in Sydney's Canley Heights.
The bodies of the two children, a girl aged three and a boy aged five, were found by their 31-year-old father when he returned home from work about 6.30pm yesterday.
The neighbour, Wendy, said she tried to resuscitate the children, who appeared "blue" to her, after the father raised the alarm.
"I didn't bring them back but I brought the mother back," Wendy told reporters.
"The mother had cut wounds to her arms and her two kids. I reckon they've just been overdosed."
Wendy said there were prescription pills and pill packets lying about the room of the family's home.
The children bore no obvious signs of injury, a police spokesman said.
A post-mortem examination will determine the cause of death.
The mother was today in a stable condition in Liverpool Hospital, where the father was also being treated for shock.
The mother will be interviewed when her condition improves, police said.
Wendy said the children's father went to her home, saying his wife was sick.
"I don't think he even knew the kids were in the bed at the time," she said.
"When I went in there, the mother had the blanket pulled right up to her chest, and I didn't see the kids until I seen the mother.
"As the father ran into the bedroom - he didn't know what had happened and he stomped on the bed - and then the little child's arm fell out from under the blanket.
"That's when I knew the kids were there - they were covered."
Wendy said the mother had tried to speak but could manage only an indecipherable murmur.
The family had lived in the home for four months, said Wendy, who rents a granny flat behind their home.
- AAP