When she left for her last world championships as a 15-year-old in 2019, there was plenty of nerves and excitement to race against the world’s best.
Last year’s Olympics brought with them the goal to perform as well as she could.
Ultimately, gaining experience was as much in the picture as a medal.
She stunned the majority of those following — even herself — as she qualified fourth for the 400m freestyle final.
And with that she put herself among world swimming’s elite.
Fairweather (18) is now bound for Birmingham and her first Commonwealth Games, with the not so small matter of the world championships in Budapest on the way.
There will be plenty of stiff competition at both.
Australian Olympic gold medallist Ariarne Titmus will line up alongside her in Birmingham.
She is skipping Budapest, but American Katie Ledecky — widely regarded as the greatest female swimmer of all time — will be there.
Also among the contenders at both will be 15-year-old Canadian prodigy Summer McIntosh, who ranks third behind Titmus and Ledecky in the 400m freestyle this year.
Fairweather ranks ninth on that list.
However, her personal best of 4min 02.28sec, recorded Tokyo, is 2sec faster than the time she set at the national championships.
She has shown her ability to perform at the big meetings and, having now proven herself against the world’s best, the goal of a medal may enter the equation.
"Definitely lots of those things we think about," she said when asked if winning a medal now became a goal.
"Obviously you don’t want to say anything or do anything around that. But it’s quite cool to know how I stack up to those people now."
The 400m freestyle is not the only race she will swim at both meetings.
At the world championships — which run from June 17 to July 3 — she will also compete in the 200m freestyle, as well as the women’s 4x200m freestyle relay and the mixed 4x100m freestyle relay.
She will swim in both the 200m and 400m freestyle in Birmingham too — the Games running from July 28 to August 8 — as well as the 100m freestyle.
While more experienced racing at this level now, she did not feel things had changed much, although she admitted it was nice to know what she was walking into.
"I think it’s fairly similar.
"I don’t think a lot of things change when you go overseas. The preparation is similar, so not really.
"There’s a bit more clarity around that and you kind of know what to expect."
While she will be Dunedin’s only swimmer in Birmingham, Fairweather will be one of three from the city in Budapest.
Caitlin Deans is already in Europe, having competed on the Mare Nostrum Tour.
She qualified off the back of a lightning 1500m freestyle swim at the national championships, while also joining Fairweather in the 4x200m relay team.
Ruby Heath will also travel to Budapest, having qualified for the open water race, a discipline she has specialised and excelled in for the past two years.
