"Mum struggled for a while and that's when I realised no one was going to help us. That's when I put everything on rugby."
The budding rugby star, who came to New Zealand on a scholarship aged 16, slept with his brothers and cousins in a hut, and lived by hunting and fishing.
"People talk about the struggles but life was great," he said.
"We didn't have much but we didn't need much. There were no TVs, no phones, no video games and that was the best part of it. We had the beach and the outdoors."
The powerful centre, who made his name with the Highlanders after starting with Auckland, had slipped out of All Blacks favour around the time he decided to leave.
Fekitoa said: "Watching the All Blacks is always hard because I know what I can do. It's difficult but, at the same time, I feel proud watching the guys.
"I didn't just decide to leave. I thought about it for months and months and I believe I made the right decision. Whatever decision you make, you've got to back it 100 per cent and go with it.
"A lot more people are moving over now but in New Zealand there is always someone coming through who can fill in.
"The game is changing. It's a business. You don't play for ever and people are starting to get that now."
Fekitoa told the Mail that "people have started talking up Ireland but I still back the boys back home."