A woman charged with the murder of a young couple and their newborn daughter over a blaze that engulfed a southwest Melbourne home has declined to appear in court.

The Point Cook townhouse was destroyed in the Wednesday morning blaze, with the bodies of three people including a three-week-old girl found in the ashes.

New mum Abbey Forrest, 19, and her partner Inda Sohal, 28, died in the blaze alongside their daughter Ivy, who was just 19 days old.

Jenny Hayes, 46, was charged on Thursday evening with three counts of murder and three of arson causing death.

It’s alleged she deliberately set fire to the Point Cook townhouse on Wednesday morning. The young family had only moved in three weeks earlier.

Hayes was due to face Melbourne Magistrates Court on Thursday evening, but her lawyer Erin Byrt said her client, who was still at the Richmond police station, had asked to proceed in her absence.

Magistrate Luisa Bazzani questioned what the relationship was between Hayes and the family, but Ms Byrt said that had not yet been disclosed.

She also declined to elaborate when the magistrate said she had been told Hayes’ state in prison was poor.

“That about sums it up at the moment,” Ms Byrt said.

The court heard Hayes takes medication for restless leg syndrome and arthritis and she will undergo a medical assessment. It is her first time in custody.

Hayes is due back in court on March 1.

Abbey’s sister Emily visited what remains of the house on Thursday, laying flowers and a Peppa Pig doll outside.

“This should be the perfect time of their life,” she told reporters on Thursday.

“Now this awful tragedy has happened.”

Townhouses on either side of the home were also badly damaged in the fire, which was brought under control in about an hour.

Three bodies were been inside the Point Cook townhouse. Photo: AAP 

Ms Forrest said the family was desperate to know what happened.

The young family had only moved to the three-bedroom, two-storey home on Totem Way after the birth of their daughter on November 13, Ms Forrest said.

Neighbours have recalled hearing screams and cries for help, with one said to have thrown an axe and rocks to break an upstairs window that wouldn’t open.

Detective Senior Sergeant Mark Kennedy also said a neighbour tried to use a ladder to rescue the occupants, but was overwhelmed by the intensity of the flames.

Ms Forrest thanked them for their efforts.

“It just makes me feel at ease that there were decent people around who were trying to help her, to risk your own life to try and help save someone in that horrible situation,” she said.

She’s set up a GoFundMe page to cover funeral and memorial costs, raising more than $8000 in less than 24 hours.

-AAP