A 4-year-old girl was clinging to her mum's leg when she was fatally mauled by a pitbull terrier in Melbourne's northwest.
The girl died from her horrific injuries and her two cousins were injured in the attack at a house in St Albans.
The dog is believed to have escaped from a neighbour's yard and entered the home where Ayen Chol and her 5-year-old cousin were playing.
Ayen died at the scene despite ambulance officers' attempts to revive her.
Daniel Atem, a cousin of one of the victims, said one of Ayen's relatives was outside the house when the dog came at her. As she rushed into the house, the animal followed her.
Atem said the dog initially attacked the 5-year-old girl and as Ayen's mother intervened, the dog then attacked Ayen, who was clinging on to her mother's leg.
"It [the dog] pulled the child from the mum ... the daughter died, the dog left the child and then the owner of the dog came after that and took the dog out," Atem said.
He said Ayen's father, who is working in southern Sudan, had been contacted and was returning home.
"He's very, very, very sad. The elders community in southern Sudan will counsel him," Atem said.
He described Ayen as "a lovely little girl, very talkative and popular in kindergarten".
Ayen's mother, Jaclin Appok, 30, is being comforted by Sudanese community leaders.
The family arrived in Australia in 2004 after spending three years in Egypt awaiting resettlement. They were living at their cousin's house after their own home burned down.
Superintendent Graham Kent of the Victorian police confirmed that the dog would be destroyed.