Kawa Sweeney's family have been told the accident has left the three-year-old brain dead.

The family, from Newport on Sydney's northern beaches, were in Bali on a working holiday when the tragedy occurred.

Kawa was flown from Bali to Perth where she was being treated at Princess Margaret Hospital. A family spokeswoman has told media Kawa has been declared brain dead by medical staff. 

She was pulled unresponsive from a pool at the family's Balinese villa on Sunday and resuscitated by a doctor from Perth who was staying at the same resort.

It took nearly two hours for the little girl to receive further medical treatment.

Her parents now face the heartbreaking decision of when to turn off the girl's life support.

Kawa was staying at the villa with her parents, homewares entrepreneur Dee Tang and artist Desmond Sweeney, and baby sister Rafa. It is believed the pool was unfenced.

The family, who is originally from Perth, received overwhelming support from the public to fly her to Perth for treatment.

After issues with their travel insurance Ms Tang and Mr Sweeney turned to social media in a plea to raise $42,000 to get their daughter on a plane to Perth.

An online campaign had raised nearly $70,000 in less than 24 hours and Kawa was flown to Perth on Monday.