The youngest daughter of the Biloela family detained on Christmas Island is fighting a serious blood infection caused by untreated pneumonia, supporters say.

Three-year-old Tharnicaa and her mother Priya Murugappan were evacuated from the island on Monday night, with the youngster suffering dangerous temperature spikes on the flight to Perth.

Her mother said Tharnicca has been sick for almost two weeks, and that repeated requests for early hospital care were refused.

Family supporter Angela Fredericks said Tharnicca has been diagnosed with a blood infection, resulting from “untreated pneumonia”.

She said the little girl is in a stable condition in the Perth Children’s Hospital, and is not in immediate danger.

“It looks like they have said she has untreated pneumonia that led to a blood infection,” Ms Fredericks said on Tuesday.

“They are continuing to run tests, as they are still not able to get her white cell counts where they should be. She is hooked up to antibiotics … they are now treating the pneumonia, while they look for any other infection sites.”

Ms Fredericks said it showed medical arrangements on Christmas Island were entirely inadequate and dangerous.

“From my understanding, this would usually show up as a chest infection, which would then get treated. And that would stop it going to pneumonia. If it went to pneumonia, that would then be treated to stop it going into the blood supply.

“We’ve had two delays in treatment here, which has led to this crisis point. Yesterday we were preparing for the worst.”

Earlier on Tuesday another supporter, Bronwyn Dendle, said Priya had pleaded with medical contractors responsible for their care on Christmas Island to take Tharnicaa to the local hospital.

She said the mother’s initial requests were refused and when Tharnicca was finally taken, after almost a fortnight of illness, hospital staff immediately ordered an evacuation flight to Perth.

Tharnicaa, who turns four next week, suffered a temperature spike on the plane to Perth and was groggy after arriving at the hospital’s emergency department on Monday night, Ms Dendle told the ABC.

“The issue was the medical contractors at the detention centre were refusing Priya’s request to get her to the hospital early,” she said.

“They were dismissing her symptoms initially as the common cold, despite persistent high temperatures and vomiting and diarrhoea.”

Home Affairs Minister Karen Andrews is under renewed pressure to resettle the Sri Lankan family in Biloela, Queensland, after years of detention in Australia. Ms Andrews, who took over the portfolio from Peter Dutton earlier in 2021, is yet to make a public comment on Tharnicaa’s medical evacuation.

The family has been held on Christmas Island since August 2019, and the town has waged a years-long campaign for the return of Priya, husband Nades, Tharnicaa and her sister, Kopika, six, who was also born in Australia.

The Home Affairs Department has said it won’t comment on Tharnicaa’s case due to privacy reasons.

But it said “health care services for detainees on Christmas Island are broadly comparable with those available within the Australian community”.

Earlier in 2021, Labor Senator Kristina Keneally visited the family on the island, off the Western Australian coast, and said the government needed to bring them back to Biloela.

“Imagine you need to deal with armed guards, you can’t get access to the medical care you believe your child needs,” she told ABC TV.

“This is the result of a government decision to keep this family in detention and to keep them away from their home in Biloela.

“That’s why it really is time for the minister to intervene and allow this family to go home to Biloela.”

The family is continuing to fight government efforts to deport them to Sri Lanka.

They were removed from their home in the rural Queensland town of Biloela and placed into immigration detention in 2018 before being taken to the island.

-with AAP