The protest was organised by a Facebook group as part of the #LetThemStay campaign concerned about the federal government's plans to deport 267 asylum seekers – including 37 babies born in Australia – back to Nauru.

Greens Senate candidate for the ACT Christina Hobbs, Senator Sarah Hanson-Young and Fenner candidate Carly Saeedi joined the protest.

Ms Hobbs said the parents felt "tricked" by Immigration Minister Peter Dutton when he had indicated baby Asha would be sent back to community detention.

"We know now that she'll be sent to Nauru," she said.

"It shows that Canberran parents realise that children in detention are just like their children.

"These parents are saying its time the Coalition and Labor listened to the medical experts and realised there is no government policy that can justify the abuse of children in detention."

Asha was released from Brisbane's Lady Cilento Hospital into community detention on Monday morning.

Supporters camped outside the hospital over the weekend to protest against her deportation.

Lawyers for Asha's family were allowed to speak to them for the first time in three days, but were still unsure of their whereabouts as of Monday afternoon.

The sit-in group's spokeswoman, Kristy Moyle, said the recent High Court ruling on offshore processing and detention had "hit a very significant chord" with parents around Australia.

"It is disappointing and shameful that our leaders have failed to protect those needing refuge for so long," she said.

The group gathered to sing Somewhere Over The Rainbow as part of the protest in front of "very understanding" police and security guards at Parliament House, Ms Hobbs said.

On Sunday Mr Dutton said Asha and her family were always going to be moved into community detention, accusing refugee advocates of "hijacking" the debate for their own purposes with some activists trying to build their media profile.

But Ms Hobbs said the protest was never about a particular group or individual attracting publicity.