Lions tour: All Blacks' band of brothers taking rugby from the farm to Eden Park

On the frosty green grass of a Pungarehu dairy farm, five brothers spent their childhoods chucking around a rugby ball.

On some days, they pretended to be Christian Cullen, running rings around each other - on other days, Andrew Mehrtens, all silk and panache.

Invariably, one would trundle inside in a tizz, tears flowing.

Yet while they may have dreamed of lifting the Ranfurly Shield for Taranaki, as their father Kevin had done, it was rare for any of them to ponder emulating their All Blacks heroes - let alone three of them, all at once.

The Barrett brothers - Beauden, Scott and Jordie - could well become just the fourth set of three brothers to play for New Zealand on Friday, should Jordie earn an Eden Park debut in their Test against Samoa.

The fair-haired trio tend to exude calm and, even when sitting in a row, speak of similar things in similar unvaried tones - process, preparation, application.

It all comes from their rural Taranaki upbringing, they believe, and the propitious genes of a rugby-playing father and an athletic mother.

"I think that if you live on a farm, you appreciate that you can work countless hours, and there's still work to be done," the 26-year-old, 49-cap Beauden said.

"We always saw Mum and Dad doing that.

"If you relate that to your rugby, it's always striving to be better and, I guess, trying to be the best you can be - and that's endless as well."

The remaining two brothers - eldest brother Kane, a former Blues back rower, and Taranaki club rugby player Blake - aren't too shabby with the footy either.

As the youngest of the five, Jordie looked up to his brothers as they made their way in the rugby world, culminating in Beauden's 2015 World Cup triumph and 2017 World Rugby player of the year gong.

He may have even picked up a few of his effortless handling skills along the way, as the ice-cool utility evaded one Barrett in the paddock, only to find another.

"I can't really remember, no-one was really supervising - I think I was hung out to dry there," the 20-year-old Jordie, a 2016 All Blacks apprentice, said.

"In a way, I've always been trying to keep up, to be honest."

Despite their proximity in the All Blacks' environment, the Barrett trio have kept apart since joining camp in Auckland on Sunday and mostly work separately - Scott in the forwards group, Beauden and Jordie with the backs.

Nor have they been made hotel roommates.

Beauden said his siblings' presence didn't change his approach to Test footy - although it may make it more rewarding.

The trio have never played in the same rugby side.

"It's not a distraction, I think it's refreshing having family in the team for the downtime but in terms of when you're training and doing the preparation required, it doesn't make a difference," Beauden said.