Four-year-old girl kept two-month-old baby brother alive after parents die in murder-suicide

The murder-suicide scene was found at a home in Chatsworth, California, on April 14. Photo / Supplied

A 4-year-old girl has been hailed a hero after keeping her baby brother alive for three days after their father reportedly shot their mother before killing himself.

A neighbour discovered the two young children unharmed but dehydrated and hungry downstairs at the family's home in the suburb of Chatsworth on April 14.

Forty six-year-old father David Kooros Parsa and 38-year-old mother Mihoko Koike Parsa were found dead in an upstairs bedroom of their Los Angeles home.

Investigators determined the murder-suicide likely took place three days prior on April 11.

"Our little angel was able to keep herself and her brother alive," Los Angeles Police Captain Maureen Ryan said of the 4-year-old.

"The baby is a miracle baby and the little girl is a hero. She's an absolute hero."

Authorities said the children are in the custody of the Department of Children and Family Services and are in good health.

Police went to the property at 9am in response to a welfare check request from a family member, but left after finding nothing amiss.

Hours after the police left, a family friend came to the house accompanied by a locksmith, and together with neighbours they gained access into the home and discovered the carnage inside.

Olivia and James Robinson, who live across the street from the deceased couple, told KTLA they knew something was wrong when they found the 4-year-old downstairs.

"She obviously was in bad condition because she reeked really bad of urine," Olivia said.

"And she had more of a blank stare on her face. She was very, very quiet."

The neighbour said when the child was asked about her parents, she said they are sleeping upstairs.

Another neighbour, Tony Medina, took in the four-year-old into his home until police arrived.

"She heard her mum crying, and then what really was kind of heart-wrenching was when she said she saw 'mommy was broken'," Medina told CBS Los Angeles.

Investigators did not release a theory as to why Parsa killed his wife and then himself.

WHERE TO GET HELP:

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