It began in 2017 with a case of mistaken identity - or so the story goes.
Jacinda Ardern became Prime Minister of New Zealand in October 2017, and it was only a month before she came face-to-face with Donald Trump - the new US President who, ideologically, couldn't be more different from her.
Trump had already congratulated Ardern on her election via a phone call, but the pair met for the first time at the 2017 East Asia Summit in the Philippines where they exchanged friendly fire - setting the stage for what would become an intriguing relationship.
"I was waiting to walk out to be introduced at the East Asia Summit gala dinner... and while we were waiting, Trump, in jest, patted the person next to him on the shoulder, pointed at me and said, 'This lady caused a lot of upset in her country,' talking about the election," Ardern told Newsroom.
"I said, 'Well, you know, only maybe 40 percent,' then he said it again and I said, 'You know,' laughing, 'no one marched when I was elected'."
Ardern and Trump met face-to-face again at the 2017 APEC Summit in Vietnam where they were joined by other world leaders from Canadian Prime Minister Justin Trudeau to then-Mexican President Enrique Peña Nieto.
The four were photographed together in their so-called 'silly shirts' and posing for the traditional family photo before the dinner where leaders could talk freely.
It was later revealed by Kiwi comedian Tom Sainsbury that Trump confused Ardern for Trudeau's wife Sophie Grégoire Trudeau - information the comedian said Ardern revealed to him backstage at the People's Choice Awards.
"I'm not sure if I should be saying this, but she said that Donald Trump was confused for a good amount of time, thinking that she was Justin Trudeau's wife," Sainsbury said at the time.
Ardern denied it played out like that.
"Someone thought the President had confused us, but in all of the conversations we had it was clear to me he hadn't, and recalled the conversation we had late last month," she said in a statement.
Ardern's history with Trump can be traced back to before her rise to power, when - as a Labour MP - she joined thousands in Auckland as part of the global women's march the day after Trump's January 2017 inauguration.
In the lead-up to the 2017 election - after Ardern had taken over from Andrew Little as Labour leader - she hit back at the Wall Street Journal over a comment comparing her to Trump on immigration.
The newspaper said in a tweet that Ardern was New Zealand's version of Trudeau, "except she's more like Trump on immigration".
Ardern called the comment "offensive".
With a few months as Prime Minister under her belt, Ardern started picking up star power as the world fixated on her youth, her liberal approach and - who could forget - the fact she was the second woman in history to give birth while in office.
"I think she's regarded here incredibly highly: young, modern, the whole working-mum thing - everything," US entertainment correspondent Sam Rubin told The AM Show in September 2018.
Appearing on NBC's Today show, Ardern revealed how she wanted to talk to Trump about New Zealand and how "we're exemplars and that we've got a record that we can be proud of".
That was in the lead-up to Ardern's next interaction with Trump at the 2018 United Nations General Assembly. But it wasn't Ardern's meeting with Trump that captured the world's attention.
The Prime Minister made history again as the first female world leader to bring an infant to the UN meeting in New York as she and her partner Clarke Gayford sat through the Nelson Mandela Peace Summit with their baby Neve.
Ardern met Trump in New York briefly at an exclusive party hosted by the President for heads of delegations on the sidelines of the UN event. The pair discussed baby Neve, Iran, US tariffs and the Korean peninsula.
Ardern made her stance on global affairs clear - that she favoured multilateralism, in contrast to Trump's anti-globalisation agenda.
"Not all will feel well-served by globalisation and the opening up of trade," Ardern said after her meeting with Trump, after the President had blasted the Iran nuclear deal in a speech to the global community.
"But it's our job to make sure that our people will benefit from trade and that we have prosperity for everyone. We can either choose to do this through isolationism or through a multilateral approach."
Ardern's global profile skyrocketed after the March 15 Christchurch terror attack.
The White House condemned the shootings and Trump tweeted his "warmest sympathy and best wishes" to the people of New Zealand. The White House dismissed the now-convicted terrorist's mention of Trump in his manifesto.
The Ardern-Trump divide had grown by July 2019 when the Prime Minister spoke out against the President for posting tweets aimed at Democratic congresswomen in the US described as "racist".
Trump said on Twitter four American congresswomen should "go back" to the countries they "originally came from", which Ardern told RNZ she "completely and utterly" disagreed with.
"We should celebrate our diversity, we do in New Zealand, I'm proud of that and so I obviously take a very different view to President Trump," she said.
It was just a few months away from Ardern's next encounter with Trump at the UN - and pressure was mounting on the Prime Minister to confront him on issues from women's rights to climate change.
Ardern confirmed she would not bring up climate change with Trump, who was in the process of pulling the US out of the landmark 2015 Paris Agreement. The Prime Minister said the focus of their talks would be trade.
Trump and Ardern were spotted seated at the same table at an event hosted by UN Secretary-General Antonio Guterres. Ardern could be seen sitting next to German Chancellor Angela Merkel.
Ardern described her roughly 25-minute meeting with Trump at the Intercontinental Hotel - on the sidelines of the UN General Assembly in New York - as "excellent".
"The knowledge the President already has about New Zealand, the warmth and high regard in which he clearly holds New Zealanders and the place, was really clear, that's a good starting point for any conversation," Ardern said of the meeting.
She said Trump expressed interest in New Zealand's gun buyback scheme.
Back in New Zealand, Labour MP Willie Jackson described Ardern and Trump as "great mates".
That was despite the two leaders' speeches to the UN in 2019 being described as "in stark contrast", with Ardern calling on the world to reject "fierce nationalism" while Trump called for an end to globalism.
Globalism was no longer the big issue by 2020 - the world was transfixed on COVID-19 - and Ardern's cautious approach to the virus couldn't have been more different to Trump's focus on keeping his country open for business.
Ardern hit back at Trump in August after the President claimed New Zealand was seeing a "surge" in COVID-19, despite just nine new cases in New Zealand at the time compared to 42,000 in the US.
"Even New Zealand, you see what is going on in New Zealand. They beat it, they beat it. It was like front page," Trump told a rally, after community cases had reappeared in Auckland. "The problem is [there's a] big surge in New Zealand. It's terrible. We don't want that."
"Obviously it's patently wrong," Adrern said of Trump's comments. "We are still one of the best-performing countries in the world when it comes to COVID and our workers are focused on keeping it that way."
Ardern went on to say Trump's comments hadn't changed her perspective on New Zealand's response and that she was still "very proud" of the country's efforts.
By the time Trump himself had caught the virus in October, Ardern was wishing him a speedy recovery.
COVID-19 has dominated both the New Zealand and United States elections. The US has lost more than 200,000 people to COVID-19 and is now battling with predictions of deaths more than doubling by January.
Ardern was re-elected Prime Minister by a landslide in October and commentators have attributed it to her Government's response to the virus. The world is watching to see if Trump will be welcomed back to the White House in the same way.