John Key and Jake Millar in Greymouth in 2011, following the death of Millar's father in the 2010 Fox Glacier plane crash.

OPINION: It was C.S. Lewis who once said "Integrity is doing the right thing, even when no one is watching."

This is perhaps the greatest lesson I have learnt from our outgoing Prime Minister John Key, a man who changed my life by doing just that.

When I was 15 years old, on Saturday September 4, 2010, my father, Rod Miller, died in a skydiving plane crash in Fox Glacier, which killed nine people.



It was the worst plane crash New Zealand had experienced in 17 years, and it tore many people apart.



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SUPPLIED John Key's card to Jake Millar in reply to his letter to the prime minister.

It was a rough time for New Zealand. The very same day Christchurch experienced its first major earthquake, destroying the city. And just over one month later, the West Coast was hit with another tragedy, after 29 men died in the Pike River mine disaster.

It was how Key reacted to these terrible tragedies, particularly the one closest to my heart, where I first began to truly respect him, and appreciate him as a remarkable leader.

Following the plane crash, Key took the four-hour return drive from Hokitika to Fox Glacier to visit the crash site, and pay his respects to the victims.



Key's humanness and kindness inspired me during this difficult time, so I wrote to him as a 15-year-old, thanking him for caring, while asking him for some advice in regards to my own future.



I was amazed to receive a very personal letter back directly from the prime minister.



Not only did he address all of my points issue by issue in an extremely kind and personal way, but he also enclosed a card, saying he wanted to meet me.

SUPPLIED Jake Millar is the co-founder of Unfiltered.

Several months later, Key, while visiting the West Coast to see the victims' families of the Pike River mine disaster, came to our family home in Greymouth for whitebait sandwiches, a cup of tea and a chat about my future.

He didn't publicise the visit for political profit. No media were invited. He did it out of the goodness of his heart, because he wanted to help, and because he cared.

It was the goodness of Key's heart that inspired me to try my hardest in life, and strive to be the best version of me that I could be.



I vividly remember being inspired by the fact that Key had lost his father as a young kid, before achieving his childhood dream. I remember thinking, 'if he could, why couldn't I?'



Inspired by Key's story, I worked with hunger and a sense of purpose to achieve my goal of becoming head boy of Christchurch Boys' High School, and head boy of Adams House, the school's boarding house, becoming the first student in 11 years to hold both roles.



I then made the decision to turn down a $40,000 law scholarship and start my first startup Oompher, which was acquired by Careers New Zealand, a Crown Entity of the New Zealand Government, in May 2010, only 10 months after I launched it.

AMY GLASS/FAIRFAX NZ Wreckage of the skydiving plane that crashed near the Fox Glacier airstrip killing nine people, including Jake Millar's father.

Today, as the co-founder of Unfiltered, I have the great honour of travelling all over the world, interviewing the biggest names in global business, growing my second startup, Unfiltered, living a dream life between Auckland and New York City.

The point to all of this is not that I'm something great, but that it's all been inspired by that early spark of inspiration: when Key wrote to me.

I remember running into Key at a National Party function years after our first meeting, and he asked how my mum's art business was going. He had only met her once, years earlier. This showed how much he truly cared.

Whether you loved or hated his politics, as prime minister, Key was a good man. He had integrity. He cared about the people he represented. He did the right thing, even when no one was watching.

When I interviewed John for Unfiltered in December 2014, I asked him what his advice would be for his 16-year-old self.

"Pin your ears back and go for it. Most people under-shoot because they're scared of failure," Key said.

"It's not ability that's going to define how successful you are, it's attitude."

"She (John's mum) believed you could shape your own life. You're the master of your own destiny," he said.

These are the lessons he taught me, and they have served me very well.

I am unsure how many lives Key has changed over the years, but I know that mine was one of them. For that, I will be forever grateful.

Jake Millar is a New Zealand­-born new­-media and education entrepreneur based in New York and founder of of Oompher and co-founder and chief executive of Unfiltered.