It's a popular bill, it has majority support in parliament, and the government doesn't want a bar of it.
Sue Moroney's paid parental leave bill has been around since 2012 and it just won't go away, despite National's plots and ploys to get rid of it, NZN reports.
It's a simple member's bill and it extends paid parental leave to 26 weeks.
When it was drawn from the ballot and passed its first reading in July 2012 the leave was 14 weeks.
National's problem was and still is Peter Dunne.
The United Future leader supports the bill, and in the previous parliament that gave Moroney a one-vote majority for her bill.
There was no way around this. Dunne couldn't be persuaded to change his mind.
Ministers tried to find another way to defeat the bill, and put pressure on the Maori Party.
That didn't work either.
The government's stated reason for opposing the bill was that it would cost too much.
Finance Minister Bill English said it would cost at least $150 million a year, Moroney put the "real figure" at $285m over three years.
There have been numerous iterations of these calculations, but basically the government says it would cost about twice as much as she believe it will.
That's almost beside the point, because it isn't the real reason.
The real reason is that there's no way the government is going to let Labour get away with passing legislation that polls have shown most voters support.
It would have to live with it for years. "We gave you 26 weeks paid parental leave" would be shouted around the country during election campaigns.
After its first reading in July 2012, the bill made slow progress.
Members' bills usually do, but this one suffered extraordinary delays.
A select committee took many months dealing with it.
National MPs on the committee asked for a time extension, saying they wanted to reconsider their position on some aspects of it.
This sounded like a breakthrough and Moroney agreed to hold it off until after last year's summer recess.
The National MPs didn't change their position and Moroney cried foul, furious at what she considered was a deceitful ploy to delay the bill.
It eventually returned to the debating chamber and was in its penultimate stage, the committee stage, in the run-up to the 2014 election.
All along, the government had the means to kill the bill.
English could legitimately use the financial veto, which exists to stop parliament passing legislation that will cost the government money it hasn't budgeted for.
But the last thing the government wanted was to be seen as mean and nasty a few weeks before the election.
The alternative was to continue delaying the bill. MPs did this by running filibusters, long and pointless debates, on bills preceding it so it didn't get to its third reading before the election.
The government won the election with an increased majority, and Moroney's bill was no longer a problem.
It was defeated on a tied vote in February.
National's relief didn't last long.
Moroney put the bill back in the ballot, it was drawn again, and then Winston Peters won the Northland by-election.
Now she again has a one-vote majority and the bill is due for its first reading on September 16.
It's all starting again, and eventually it will end the way it would have if National hadn't been able to delay the bill.
English won't confirm it, but he will use the veto on the bill's third reading.
Moroney will lose the bill but she can claim successes along the way.
Since it first appeared the government has increased paid parental leave to 16 weeks and it will rise to 18 weeks in April next year.
It has a bill in parliament that will widen the categories of woman workers who can apply for paid parental leave.
And it is negotiating with ACT's David Seymour to extend paid parental leave to women who have premature babies, multiple births or babies with disabilities.
Moroney offered that as a compromise when National was blocking her original bill. It was rejected.