"When Kobe and his twin Zac were five years old I would get them to tackle calves," Kobe's father Jason Hetherington told AAP.
"I'd be doing all the cattle work and with the calves that I'd brand and let through I'd say, 'go and tackle them boys. Wrangle them, jump on them and ride them'. They would get in there and bulldog them and scruff them.
"They were good at it too. They were determined, put it that way. As a little fella the fear side of things never worried Kobe. He'd give most things a chop and think about it afterwards."
It was an unorthodox initiation on tackle technique, but no surprise for those who know Jason, a drawling Queensland old salt who won the 1995 grand final with Canterbury.
The former Maroons hooker brought Kobe up tough in the small town of Baralaba, which was also the early home of Broncos winger Corey Oates.
Kobe, 24, will play off the bench in Sunday's NRL grand final against Penrith with fond memories of early life on the cattle property, which the Hetherington family still owns.
"Growing up we didn't have too many facilities so Dad used to get us into the yards and he would separate heifers from the calves," Kobe said.
"He'd get us in there and say, 'go wild'. Me and my brother would tackle them. Growing up we did stupid stuff like that and looking back I'm sure it helped me get where I am."
Kobe once referred to his father as being "tough as a two-dollar steak", but his soft side came out in the dressing room when the Broncos won their preliminary final 42-12 against the Warriors on Saturday night.
"He's extremely proud. I saw a few tears roll out of his eyes. I've just got to get the job done now," Kobe said.
Australia's defensive coach and two-time premiership winning Broncos forward Trevor Gillmeister told AAP that Hetherington was amongst the best defenders in the game.
"Kobe cuts them in half with the way he gets in under the ball. He's been a big part of the Broncos' success," Gillmeister said.
Kobe's approach led Broncos skipper Adam Reynolds to tag him the team's cattledog.
Defence is a job Kobe takes seriously and will need to do well on Sunday when Panthers battering ram Spencer Leniu also comes off the bench.
"He's a quality player but the bigger they are, the harder they fall. I'll just get into his legs," Kobe said.
Kobe suffered a biceps injury in pre-season and eventually fought his way into the side in round seven. He's been a permanent fixture ever since.
"He had that injury and missed the start of the season and I have admired how he bounced back as a young fella from what was his first real injury," Jason said.
"I've had four shoulder reconstructions, eight knee ops, both groins cut out, a broken jaw, a reconstructed hand and two hernias.
"Injuries test you but he has come back really well. That was a good learning curve for him."
Jason played in three grand finals (1994, 1995 and 1998) for the Bulldogs and knows how hard they are to win.
The 1998 grand final was won by the Broncos with current coach Kevin Walters and Allan Langer in the team.
"It is ironic that my young bloke is playing in a grand final 25 years later for Kevvie and Alf who beat us back then," Jason grinned.
"One NRL game is hard to win, let alone getting to a grand final. It is a special moment for Kobe, our family and the Broncos.
"He had a dream. This is what it is all about."
Kobe was playing third-tier footy for Valleys in Brisbane in 2019 and considering taking up a job in the mines before the Broncos gave him his NRL chance, after he had been in their system as a teenager.
Kobe's parents Jason and Kym, brothers Zac and Eli and sister Laynii will all be on hand at Accor Stadium on Sunday.
"It's pretty crazy. I never thought I'd even play NRL, so I am just extremely proud and humbled by the opportunity to play in an NRL grand final," Kobe said.
"You have got to take every opportunity in these big games. With my role off the bench I am just going to run hard and tackle hard.
"All of my family are coming down which is unreal. It will be good to get them into the sheds after the game."
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