Winston Peters says he has serious concerns for Todd Muller's mental health.
The New Zealand First leader told The Country he has a lot of time for Muller and wishes him the very best.
"In this case, I'm told he had a serious breakdown. That happens in families.
"We can make all the speculative statements we like, but frankly, my sympathies go out to him, his family and his children.
"He's a good bloke, and it happens, and there but for the grace of God go you and I."
Peters says he isn't worried about the prospect of having to go up against new National leader Judith Collins at the next election.
And the Prime Minister is spending the "bare minimum" of her time thinking about the upcoming election.
Jacinda Ardern said she accepts there is an election this year and that there will be politicking, but her focus is on the pandemic.
"My time, my energy is focused on Covid-19."
Ardern said politicking will not mean much to New Zealanders, who will be expecting the Government to focus on the Covid-19 response, and she hasn't spent much time thinking about squaring off with Collins.
National MPs met this morning to discuss changes in the party, which will include a reshuffle of some portfolios, Collins says.
The future of health spokesman Michael Woodhouse is in question, after Collins today refused to publicly say he would be keeping the job.
Asked if he would continue in the health portfolio, Collins would only say "there are still a few things to work out".
Woodhouse said yesterday that he had no plans to follow Muller and step down.
"My focus is entirely on the next 10 weeks," he said.
Collins is downplaying the significance of the changes, saying it would only affect herself, her new deputy leader Gerry Brownlee and "a few other people".
Speaking to media this morning, Collins would not elaborate on who these "other people" would be.
She has confirmed that Paul Goldsmith will retain finance and that former leader Simon Bridges will continue in foreign affairs.
Last week, National MP Hamish Walker was forced to resign after he outed himself as the leaker of sensitive and personal Covid-19 information.
As it turned out, Woodhouse had received similar information from former party president Michelle Boag.
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Collins said she would be "talking to Michael today".
"We'll be getting some information on that and then I'll be making a call," she told RNZ.
She said she was taking the issue "quite seriously" and was "absolutely not at all comfortable" about the leaking of patients' details.
If Collins strips Woodhouse of health, Whangārei MP Shane Reti would be the most likely candidate to take his place.
Reti – a medical doctor – has been heavily involved in National's health response and policies.
Speaking to MediaWorks, Collins said National would now look at "some of the mild changes we need to make".
"Gerry and I have now got other jobs to do and we need to shift a few portfolios around.
"We also have to take into account that Nikki [Kaye] is back doing education in such a big way but also just to make sure we've got something available for Todd as well."
Collins said the party will be having a discussion about whether or not Muller would be on the front bench.
She has not yet spoken to Muller about this – "but I think we will certainly be wanting to talk to Todd about his options".
She said there wouldn't be many changes, given the election is only a few weeks away.
"I don't want people having to chop and change portfolios right before an election – I think that's a bit foolish."