Friends have paid tribute to a mother and daughter found dead at home in separate rooms, as police investigate the mysterious circumstances.

Jennifer Carrig, 53, and her 13-year-old daughter were discovered inside the property in Marsfield, in Sydney’s north-west, on Thursday morning.

Police established a crime scene at the suburban home, but said there was no evidence of violence.

Carrig’s best friend Samantha Thomas-Barber told The Daily Telegraph she was the “best mumma” to her family.

It has been reported that Carrig’s daughter required full-time care.

“She was the best; so caring and thoughtful,” said Thomas-Barber. “A true treasure and warrior.”

Friends have paid tribute to ‘best mumma’ Jennifer Carrig. Photo: Facebook

A family friend told Daily Mail Australia that Carrig took him in when he was homeless.

“I can’t believe this has happened,” the friend said.

“Jen has lived here her whole life and that home was supposed to go to her children.

“The fact that [the daughter] has died is just messed [up].”

The friend said he rushed to the house as soon as he heard the news.

“When I got the call while I was at a motorbike driving test, I jumped in an Uber and came straight here.”

Police are investigating the mysterious circumstances. Photo: AAP

Forensic officers were seen carrying evidence bags on Thursday afternoon, stepping over police tape across the driveway of the two-storey brick home on Menzies Road.

A swing set and netted trampoline could be seen in the home’s front yard as detectives moved about the scene, one of them inspecting what appeared to be a surveillance camera.

A crime scene has been established in the quiet suburban area, with police awaiting an autopsy report as they investigate the deaths.

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