Father Charged With Murder After Boy Tragically Dies In Domestic Stabbing

The boy's father has been charged with murder by police, who described the crime as "it's about as bad as it gets".

UPDATE: Police charged the boy's father with murder on Friday afternoon, and he has been refused bail. He will appear before Parramatta Bail Court on Saturday 9 June.

A five-year-old boy has died after allegedly being stabbed by his father in a domestic-related dispute in Sydney on Friday.

The boy was seriously injured after a domestic dispute in Carlingford, in the city's north-west, around 7am, according to NSW Police.

Police said the boy and his grandmother fled the scene and raised the alarm. The boy was taken to Westmead Children's Hospital under police escort in "a very urgent and high-speed run".

However, police later confirmed to Ten Eyewitness News that the boy died in hospital at 8am.

Superintendent Rob Critchlow said at a press conference it was a "horrible and brutal crime" committed against the boy, with a "horrendous" level of violence.

"It's about as bad as it gets," Critchlow said.

"All we know for sure is that a young child has been murdered in his home brutally."

The boy's grandmother, aged in her 60s, was treated by paramedics for shock.

A 36-year-old man, who police say is known to the child, has arrested and two crime scenes have been established. Inquiries are continuing.

Police praised the actions of the boy's grandmother in helping him from the scene, calling her "heroic".

"She's behaved in a heroic and caring manner, as you would imagine a grandmother would. She's been presented with something terrible, and done her best to get the young boy to safety and to get him treatment," Critchlow said.

"Sadly, despite her best efforts, there was nothing more she could have done. We're grateful to her for what she did do at the scene."