Some 11 children have been transferred to Australia from the Nauru detention centre to receive medical treatment.
They are the latest to be moved amid a mental health crisis on the island, which has long been plagued by allegations of human rights abuses.
The tiny Pacific island nation is the site of a controversial Australian processing centre for asylum seekers.
Australia has been criticised for holding child migrants who have mental heath issues on Nauru.
Doctors and human rights have called for all child migrants and their families to be evacuated from the island. Fifty-two children remain there, according to official figures.
The 11 children join more than 600 people in Australia on “temporary transfers” from offshore detention, reports say.
It is thought to be one of the largest groups to be transferred since offshore detentions began in 2013.
Can they stay in Australia?
Under a controversial policy, asylum seekers intercepted while travelling to Australia by boat are banned from ever resettling there.
Home Affairs Secretary Michael Pezzullo said permanent asylum in Australia would not be granted to those transferred for medical treatment because it could encourage “perverse behaviours”, including causing serious harm to instigate a transfer.
“Treatment in Australia is absolutely available for those who require it,” he said on Monday.
People who have received medical transfers live with persistent uncertainty about whether they will be forced to return to Nauru, the UN’s refugee agency has said.
Recent attention has focused on child migrants in the Pacific nation, who suffer from mental heath issues which have led to cases of self-harm, said the doctors’ group, Médecins Sans Frontières.
How many migrants are there?
Many of the children on the island have lived most of their life in detention, with no idea of what their future will be.
Some 652 people – including 52 children – are still left on the island, according to the latest official figures; they are made up of 541 refugees, 23 failed asylum seekers, and 88 people of undetermined status.
Prime Minister Scott Morrison is poised to lose his one-seat parliamentary majority after voters on Saturday shunned his ruling Liberal Party in a by-election.
Two independent MPs said on Monday their support for Mr Morrison’s shaky government was tied to the fate of the child detainees on Nauru.
The Nauru detention centre was set up by Australia in 2013 in a controversial deal to house asylum seekers intercepted while trying to reach Australian shores by boat.
Australia says they will never be able to resettle in Australia, so over the years has sent many to privately run “processing centres” it funds on Nauru and in Papua New Guinea.
Canberra maintains its policy prevents deaths at sea and discourages people smugglers but the tough stance has been widely criticised.
Can they go to New Zealand?
In response to public pressure, Mr Morrison is reported to be considering taking up a long-held offer by New Zealand to accept 150 refugees.
The government has previously refused the offer, arguing it would be a “back door” for refugees to make it to Australia.
It could soften its stance if new legislation is passed to limit the travel to Australia of refugees accepted by New Zealand, according to local media.