After watching eldest son Jack make his debut earlier this year, Matty Johns’s younger boy Cooper gets his chance on Thursday night.

And as fate would have it, they could be lining up against each other in a fortnight.

Cooper Johns, a 21-year-old halfback, will make his Telstra Premiership debut for the Storm against Parramatta at Bankwest Stadium on Thursday night after Jack broke into the NRL last month for Souths.

Jack, a 23-year-old second-rower, has been selected on the interchange bench for the Rabbitohs for what will be his third match on Saturday against Manly.

If the brothers can keep their positions, their respective teams face off when South Sydney host the Storm in round 17.

Matty told jetwinvip.com at a Fox League function earlier this year that he and wife Trish would go through “interesting times” when their sons are living their dream of playing in the NRL.

"What's really important in my relationship with my boys is that I don't distance myself, but they need a father not a coach," the Fox League host and analyst, as well as a former NSW and Australian representative, said.

"And there is a temptation to speak up because things you went through in your career, you can see a pothole just ahead.

"You see it coming but I've got to have the discipline to let them hit it, and go through it. That makes for a better relationship.

Cooper Johns receives his first Storm jersey

"I'd rather sit on the couch with them and talk movies, talk music, that kind of thing."

Their father played his younger brother Andrew Johns just once – round six in 2002 when the Knights thrashed the Sharks 52-8.

But like the personalities of the senior Johns brothers, the younger siblings are vastly different.

Matty Johns likes to watch from afar and leave his sons' development to their coaches. ©NRL Photos

"Jack is quieter, more sensitive and sensible. Cooper is more of a scallywag," Matthew said.

"If my older bloke sees a camera, he shies away from it. My young bloke would move to the centre of the frame – it's just his personality."

If their paths do cross, Johns might find himself having to analyse their games in his various media roles.

"I'll just give it to them and say 'They're not as good as their father',” Johns said.

"Honestly, when they first played junior football and started to show their skills, that's when I felt the pressure start.

"But now when I watch them play I'm really at ease. They are at a point in their lives when they understand their own games.

Storm signals: Eels unfazed by horror record

"And you couldn't ask for two better coaches," he said, referring to Wayne Bennett at South Sydney and Craig Bellamy at Melbourne Storm.

"They are at strong clubs so I don't need to say anything.

"And when people ask me 'How are your blokes going in first grade?' I say 'I don't really know because I'm not coaching them. Ask Craig or Wayne'."