Dr Justin Coulson details the four things a child should know when faced with a situation of bullying

When it comes to witnessing a bully in action, parenting expert Dr Justin Coulson said the most important thing you can do is teach your child to be an "upstander", not be a "bystander."

"85% of bullying instances there are bystanders present," he explained. "That means that we can make a difference by teaching our kids what they can actually do when they see it, in a way that keeps them safe."

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In Episode 2 of the new season of Parental Guidance, the children took part in a challenge that saw two undercover actors act out a scene involving bullying.

The different parenting styles were put to the test as the children reacted to the drama unfolding in front of them.

EP 2 RECAP: How far is too far when it comes to dealing with a bully?

"This challenge tests how the children behave when confronted with a bullying style situation," Justin confirmed. "Have they been taught to avoid the conflict, or have they been taught to step up, intervene and do what's right?"

You can watch the challenge and Dr Justin's advice in the video above.

In a heart–warming turn of events, every single child had the confidence to stand up for the child being tormented, each in their own way, but each strong and clear in their stance that the behaviour in front of them was not OK.

"Having experienced bullying as a child, I really want to equip my children with the ability to handle bullying," shared Gentle dad Marcus, as his wife added they taught their children to always treat others with kindness.

Put to the test, their son Levi did just that. "He just showed us how you parent, in the way that he handed that," marvelled Unstructured mum Melody.

"There are a lot of things we can do to help our kids when it comes to bullying," Justin said. He believes we can help kids become upstanders by teaching them just a few steps:

• Tell the bully to stop

• Involve other bystanders to help direct the bully away

• Help the victim extricate themselves

• Finally, report the behaviour to a safe adult

While the children handled the challenge well, unexpectedly, the parents later argued about how best to handle a bully that was being physical.

"This challenge was one probably the best example of where the kids just shone," Justin revealed in an exclusive interview with 9Entertainment. "But all of a sudden, we had these unexpected confrontations in the in the room with the parents, where there's this clash of values. That was a really, really tricky one."

The heated debate began when Outback mum Tency said she would give her kid a high five if he defended himself against an unrelenting physical attack.

"If it comes to it, and they're putting their hands on you and the teachers aren't doing anything, then you're allowed to retaliate," she said.

"Good smack in the face is going pull 'em up pretty quick."

The comment was met with controversy, as parents around the room struggled to reconcile themselves with her stance, while Tency explained it should be considered as a "last resort."

Unstructured mum Melody was firm that increasing the physicality was not the safest option and the Lighthouse parents agreed violence shouldn't be tolerated at all.

But American mum Kim felt sometimes, returning fire may be the only course of action. Road School mum Amy agreed. Interestingly, even Slow Style parent Philippa said she could see the dilemma and the answer wasn't entirely clean cut. "I really want to say 'no violence', but if my son or my daughter was getting hit then…" she trailed off.

Watch the parents debate the scenario in the clip above.

Justin explained how parents might instead approach the complicated issue.

"When bullying becomes physical, things can start to get really scary," he said.

"But rather than telling our kids to hit back, we can tell them to do only what they need to do to block the attack and run."

Parental Guidance airs Monday and Tuesday 7:30pm Channel 9 and 9Now.

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