Oranga Tamariki usually investigates complaints at a local level, but complaints relating to a child uplift or the safety of a care placement will now go to a team that is independent of the local site.
A family advocate, Michelle Keefy-Tai, who has helped many whānau navigate Oranga Tamariki's complaints system, is optimistic about the changes.
But she said complaints needed to be dealt with quickly.
"It needs to be looked at straight away, simple as that, especially with whānau who are still going through these court proceedings.
"That complaint should be looked at within 24 hours, 48 hours maximum, because that complaint could be the saviour for our mokos, for our babies, who are going to go into placements."
The new team is one of the many changes Oranga Tamariki has made since an internal review found it made a raft of failings when it tried to take a newborn baby from a Hawke's Bay mother last year.
It's now more difficult to make an application for a without-notice uplift, requiring additional checks before the uplift is signed off.
In a statement, the ministry said of the 350 cases it was currently reviewing, 17 were being handled by the national team.
"Our centralised complaints process is specifically focusing on any potential pre-judgement or misuse of authority, the processes around decision making, and reviewing the information put before the Family Court.
"This team is in place to ensure that any complaints that are potentially serious in nature are flagged to be thoroughly and independently reviewed at the start of the complaint process."
A Christchurch mother isn't convinced the new national model will work, because many whānau are afraid to complain at all.
"Lots of people are so scared, like, if I make a complaint they're not gonna give my kids back or if I make a complaint they're gonna come after my other children," she said.
"That was my concern, that they were gonna come after my son now."
She said several complaints she has made to Oranga Tamariki have either been ignored or not been investigated.
She also said complaints relating to children in state care must be dealt with by a group independent of Oranga Tamariki.
"Someone who can look at the files and look at the story and be honest. Obviously someone who is independent," she said.
"They conveniently lost my first complaint so I went back to my local MP and we did another one and she sent it in for me so it was a bit harder for them to ignore."
Oranga Tamariki said the outcome of the 17 reviews would not be made public.
The Ministry said there were a range of options for people who did not agree with the outcome of a complaint, including the Ombudsman, Children's Commissioner and the Social Workers' Registration Board.