A five-year-old boy allegedly raped on Nauru may win a temporary reprieve from being returned to immigration detention on the Pacific island.
But 90 other children - including 37 babies - along with 160 adults face a return if the High Court validates the legality of Australia's offshore detention regime.
The court will make its decision public on Wednesday.
Ahead of the decision, Immigration Minister Peter Dutton insisted the government acted in the best interests of asylum seekers brought to Australia from Nauru for medical treatment.
"We're not going to send people into harm's way," he told Sky News.
The ABC has aired concerns by paediatrician Karen Zwi who says the boy suffered serious mental health problems after the alleged sexual assault and began to self-harm.
Dr Zwi said the child's greatest fear was returning to Nauru.
"That is this huge cloud hanging over him that he will be returned to an absolutely traumatic and devastating environment for him," she said.
Mr Dutton said his department, in making the decision whether to return the boy, would take into account medical advice.
"If people need prolonged support they receive it," he said.
"We've provided significant support for a number of people who have come to Australia because they can't get the requisite medical needs in Nauru or in PNG."
But Mr Dutton said the government had to be mindful of the message being sent to people smugglers.
Although, he wanted to reduce the number of children in detention to zero, people smugglers were channelling a message to potential customers that "Dutton's a soft touch and you can put women and children on boats and be successful".
The minister was reluctant to speculate on what response the government would make if the High Court challenge was successful.
Shadow attorney-general Mark Dreyfus said Labor, when it set up the offshore processing system, did not envisage that two-and-a-half years later more than a thousand people would be languishing in indefinite detention.
"We've heard nothing from Mr Turnbull, nothing from Mr Dutton that in any way offers any prospect to any of those people that this indefinite detention is going to be brought to an end," he told ABC radio.
Mr Dreyfus refused to say if it was time to end offshore detention, but argued the government had to do a "great deal more" to stop people being held indefinitely.
"This present situation can't be allowed to continue."
