The Government has announced major changes to state care to try and prevent long-term trauma for young people.
They will now be allowed to stay in the care of Child, Youth and Family (which will become the Ministry for Vulnerable Children in April) until they're 21, rather than being kicked out at 17. The change will be phased in over five years.
"Today they would be told thank you very much, you've had a good life - off you go, you're on your own," Social Development Minister Anne Tolley told Paul Henry on Wednesday.
"Seventeen is pretty young to be out there on your own. Many of them are still at school, doing their final year."
It comes after a review found 90 percent of children placed in state care end up on a benefit at a young age.
"The life outcomes for these young people are truly dreadful," says Ms Tolley. "It's a huge cost for their lives, and it becomes a huge cost for the taxpayer."
Those in state care will also receive advice and support until they're 25.
"We're going to require the new Ministry [for Vulnerable Children] just to keep tabs on them and check up every now and then and make sure they're okay - just like a real parent," says Ms Tolley.
"They will stumble and fall - we see it with our own children. They'll make a mistake, it won't work out, but they'll have somewhere to come back to."
The new Children's Commissioner praised the initiative.
"It's a very principled and very far-sighted thing to do. If the new agency Oranga Tamariki is going to be visionary and world-leading, that had to happen," Andrew Becroft said, using the new ministry's Māori name.
So did Labour, saying it has lobbied for the age to rise for several years.
"For these young people the state is their parent, and no parent cuts off their child at a particular age," says social development spokeswoman Carmel Sepuloni. "This announcement will give the young people the option to return for support at the age they need it."
The Greens have doubts the Government will properly fund the initiative, which is otherwise a "good step".
"The families that need help with their kids also need a living wage, healthy and secure housing, and access to high quality early childhood, primary and secondary education," says social development spokeswoman Jan Logie.
"More resources need to go into supporting families and whānau to keep children within their care. Within CYF, there aren't enough social workers to support the carers, and families are left waiting."
The cost isn't yet known, but in the long-term Ms Tolley says two dollars will be saved for every one spent.
"About 500 children leave care now every year - not all of those will want that. We're estimating about 30 percent will probably continue - it could be as many as 50 percent. It's going to cost millions."
Ms Tolley hopes to have the new legislation before Parliament by the end of the year.
Despite the state care age lifting, there are no plans yet to raise the youth justice age to 18. Labour says there's a "crossover" of young people in the state care and youth justice systems, so it makes sense to align them.
"Not only does separating these two ages in law mean that New Zealand will continue to breach the United Nations Convention on the Rights of the Child, it also presents practical difficulties," says Ms Sepuloni, because it will add "administrative complexity".