In year 12, he decided he wanted to do a fine arts degree but hadn't worked hard enough. So he spent a year working in the trade, did a few sewing courses, taught himself to draw and suddenly he knew that's what he wanted to do.

He's always believed he'd be successful. He's single-minded and has that artistic nature where the practicalities get swept aside. He hadn't thought through how he'd achieve what he wanted without the business knowledge and money behind him. But then it all happened so quickly. His first year out from TAFE, he started getting orders for his women's clothing from small boutiques. He was trying to fill orders from his tiny bedroom in our home in Newtown [in Sydney's inner west], and I did a bit of everything: cutting, and sewing on buttons.

He had his first solo show for Fashion Week in 2009 in an underground carpark in Kings Cross, which was incredibly exciting, scary and emotional. The following year he was the first designer to hold his Fashion Week show in the Sydney Opera House.

Sometimes it was stressful, and when it became too much for him I'd ask, "Do you really want to do this?" He never wanted to compromise on quality. I used to try to argue, but he's hard to say no to and he's so passionate. We have a close relationship.

There's a vulnerability there I worry about sometimes, because of the pressure, and in design you're subject to criticism.

In 2014, I remember unloading dummies and clothes in Sydney's Pitt Street in the middle of the night when Dion opened his first store in Sydney's Strand Arcade; it was an exciting and surreal experience. [He now has nine stores in Australia, and an office-studio in New York.]

I guess I always knew he'd go overseas. I'm hopeful he'll come back. He's not very good at communicating, but he did ring me for Mother's Day from LA airport.

A lot has happened in 10 years, but some things don't change. Dion's always running late, he doesn't plan ahead, he loses keys, he loses everything!

I find it amazing they're teaching about him at TAFE and colleges – he's so young, although I guess he's not that young anymore. Maybe we'll say he's grown up when he stops losing keys and things.

DION: My mother home-schooled me for a few years, which created a special bond. We were away for a few years exploring, which I hated at the time because of the constant disconnection. We'd go to school, make friends, then keep moving – but in retrospect I appreciated it. My parents divorced when I was a teenager and I lived with my dad for a bit, then with Mum when I went to high school. Dad and I are really close and he's been super-supportive. My mum is innately creative and has always been supportive in all the things I was interested in, exposing me to different art, culture, design and theatre.

Fashion is what I care most about. I talked about it with my mother but never had the "I want to be a designer and start my own brand" conversation. When I did start out, I remember her asking, "Are you sure you want to do this?" She was cautious for me. I didn't listen. The first two years my business was just me, a few friends helping out and Mum helping in any way she could – managing the finances, helping fund the production – but it was all new to her too. By the time I'd shown my first independent collection, I had a lot of industry pressure and expectation and didn't really know what I was doing. I was only 23. It was stressful and Mum's support was great – a lot of the time, it was just her presence and having someone to talk to, because I was putting a lot of pressure on myself and struggling to deal with it.

Around three or four years in, I considered quitting. I was under so much financial stress and didn't have the infrastructure to do what was needed. We were growing exponentially but there weren't the funds to resource the business properly, even though we were getting big international orders. It got to the point where I felt trapped and that I would be failing either way – if I exited and let people down; or if I stayed. Cue Clothing Company invested in the brand, helping it grow.

When you've put so much of yourself into things and they're negatively reviewed, it can be tough. There have been times when that's taken its toll, but I talk to Mum about that because she's one of the few people who understands and is objective. Over the years, my skin has got thicker. We've been through a lot together. I wouldn't be where I am today without her emotional and financial support.

To read more from Good Weekend magazine, visit our page at The Sydney Morning Herald, The Age and Brisbane Times.