Nathan's mum Leanne knew there was something special about her child when at just four months old he would greet people with a "hello".
"Being my first child, I didn't realise that it may not have been normal for my three-month-old to be saying 'hi' to me, although it did surprise me at four-months when he starting greeting people with 'hello'," Leanne says.
"When he did that, I was looking around trying to figure out who said it, not expecting it to be Nathan!
"It took me four years to catch on that his largely self-taught reading, spelling, writing, maths (including multiplication and division past the 13 times tables), and geography before starting school, may be more than just a clever child.
"When we had Nathan assessed at four years of age for school planning purposes, we discovered he was in the top two per cent for his age for quantitative reasoning."
However, it was only after the now 12-year-old from Brisbane auditioned for SBS's new show Child Genius that his family discovered Nathan was gifted.
"After filming wrapped up he asked to have a new IQ assessment to help him understand himself better," Leanne says.
"It turns out he has an IQ of 137 (gifted) and he was accepted into Mensa. That was another surprise."
Presided over by quizmaster Dr Susan Carland and presented in association with Australian Mensa, Child Genius is a six-part series bringing together 19 gifted children aged seven to 12 from all over Australia.
In a unique competition documentary format, it will showcase the phenomenal academic achievements of these ultra-smart kids.
Leanne entered Nathan, who wants to be an engineer, in the hope it would help him make new friends.
"Socially, being gifted has had a mixed impact on Nathan," she says.
"On the one hand, some of the kids in his small primary school would try and keep up with him in maths as a friendly challenge; but on the other hand he struggled to have much in common with kids his age.
"His kindergarten teachers would give him multiplication and division (or adding numbers in their tens of thousands together) to do whilst his peers built sand castles."
Despite trying to "fill in the gaps" by taking him to activities that interested him, such as Astronomical Society events, many of his peers were adults and the events were often held late on school nights. Nathan's other big love is cubing.
Nathan agrees that while being gifted comes with lots of benefits, it also has its difficulties.
"Some of the best things about being gifted are being able to help people with their work and get good grades and awards at assembly," he says.
"Some of the most challenging things are being teased as a 'nerd' by some people and finding it hard to make new friends of similar intellect to me."
Leanne says the family has no regrets about Nathan taking part in Child Genius.
"When Nathan's audition was successful, I was keen to use the opportunity for Nathan to meet some like-minded peers, and to have some fun as a family," she says.
And he met a bunch of fabulous kids.
"Nathan hit it off straight away at Brisbane airport with James, another contestant, when they both pulled out their speed cubes whilst waiting for the plane to the audition," Leanne says.
"All the kids from the show (and the parents) also keep in touch on WhatsApp.
"It's great for the kids to have a forum to celebrate their successes, as it's largely not socially acceptable to celebrate achievements (except perhaps sport) in other social settings."
Nathan agrees the best thing about taking part in the show was the new friendships he formed.
"The most enjoyable thing was making lots of new friends with similar interests, especially James as he and I both like cubing," he says.
Chairman of Mensa's International Gifted Youth Committee Alan Thompson said around 10 per cent of Australia's population would be classified as intellectually gifted.
"Research has shown that parents are excellent at identifying intellectual giftedness in their child, sometimes even within the first few months," he says.
"Besides having an advanced brain, high-ability children can't really be generalised: they are unique individuals.
"Some traits to look for include a prodigious memory, rapid learning, a great sense of humour, a strong curiosity, and sensitivities to both physical and internal worlds."
If you think your child is gifted then seek out a qualified psychologist specialising in testing for gifted children.
"Gifted children are extraordinary humans living in an ordinary world. They need to be able to find and recognise their own tribe," Mr Thompson says.
"Seek out the plethora of resources available both nationally and internationally, and start building a community to support your high-ability child.
"They require completely customised learning, including acceleration options at school. And they need whatever resource they are currently obsessed with: help them fulfil their rage to learn."
Child Genius airs from Monday 12 November, at 7.30pm on SBS and SBS On Demand.