Harper's star has risen steadily over the last six months and looks set to make his first-grade debut in the Bulldogs' season opener against the Warriors in his native New Zealand on March 16.

The last two years have been a whirlwind for the humble and politely-spoken father of two from Ngaruawahia, which has a population of a touch over 5000, in the Waikato region on the North Island.

When he accepted an offer to take up a contract at Belmore in 2017, after standing out at a high performance camp, he didn't know what to expect from life in Sydney.

"I'd never been around big cities. I've travelled to big cities but to work here was different," Harper told AAP.

"I took it on as an opportunity, I had to take it on. It's heaps different to home. The amount of people and what goes on.

"Traffic's the worst mate. Honestly there's no traffic lights (in Ngaruawahia). There's two roundabouts in the whole town."

Three years ago his life changed when he became a father to twins at just 17, an experience which has come to drive his desire to make it in the NRL.

"I've got two young kids and I want to be a bit of an example to them," Harper said.

"Coming from a small town like Ngaruawahia, if a young fella like me can make it, why can't they.

"I also just love playing football and want to get better and better."

And improve he has.

He spent a year in the under-20s before graduating to the NSW Cup last year.

He came up with the match-winning play in the Bulldogs' reserve grade grand final victory, producing a one-on-one strip on Newtown's Matt Evans before racing 15 metres to score and break a 12-12 deadlock with nine minutes remaining.

And before his departure to Cronulla, Morris singled out Harper as the leading contender to take over his spot in the backline in 2019.

"I was pretty stoked to hear that coming from a player like Josh, he's played Origin and for Australia," Harper said.

"For him to see potential in me, it gave me a lot of confidence going into the (NSW Cup) finals. It gave me belief that I could one day play NRL."

Australian Associated Press