Although he retains the surname Vaea, the ACT Brumbies No.8 has the family name of his mother and father, Tutuila, tattooed on his right bicep.

The pair will be at their hometown stadium in Brisbane on Saturday night to watch their son play the Queensland Reds in a Super Rugby match many thought would not be possible for him.

Vaea is only four games back from life-threatening blood clots on his heart, discovered in late 2012. The cause is still a mystery, something the 26-year-old constantly questioned during a drawn out two-year recovery.

"Why me? ... I've asked so many times but no one's given me the answer," Vaea says.

But Vaea says he will never ask his birth parents the other big question about his life: why they sent him from Australia to Tonga, before he could remember who they were, to be raised by his grandparents.

Vaea was 12 before he found out who his real parents were, when the woman he called mum told him she was actually his grandmother.

"I will never ask, I can just picture in my head why [my parents] sent me there," Vaea says.

"I don't like asking why, I just appreciate what they do. I tell myself there's got to be a reason they sent me to Tonga. I think they were doing the best for me, that they sent me there for a reason."

Vaea is more than half-an-hour late for this interview. When he arrives he's wearing thongs, shorts and a loose-fitting red T-shirt, no doubt purchased last year when he was still on blood-thinning medication, virtually inactive and weighing more than 150kg - 30kg heavier than he is now.

His slanted smile, from chipped front teeth, adds warmth to his expression, actually giving him a cheeky, jocular introduction.

Vaea quietly excuses himself, he's been at the credit union transferring money to Tonga, to his grandparents he thought were his parents until he was almost a teenager.

"Not every pay-cheque, but sometimes they need a bit of help," he says. "Growing up as a child I thought they were my parents, but unfortunately they're not. But I was very grateful. You've got to give something back to them.

"I know they don't want anything from me, but it shows my appreciation and how lucky I am for them to help me grow up, to make me the person I am now."

Vaea is the surname of his grandparents, Anna and Fine, who raised him in the small Tongan village of Kolovai. It's known by tourists for its colonies of flying foxes, considered a sacred animal in the island nation.

Vaea is also the first name of his real father, who lives in Brisbane with his mum, Hayley.

A talented young rugby player in Tonga, it was only when he accepted a boarding school scholarship to New Zealand's Nelson College that Vaea learned of his true family history.

"Just before I got on a plane, grandma had to sit me down and tell me this is your real mum and dad," he recalls. "I was like 'what? Who are they?'.

"It did take me time to get used to it. You grow up as a child and these are your parents, then next minute it's 'hold on, what's going on here?'. I think I adapted very well.

"I still think as grandma as my mum in some way because I was raised by them. I called her mum before I realised she was my grandma. Now, instead of grandma, I call her Ma.

"I have no anger against them. People say things happen for a reason and I believe it. Even when I got injured, I don't like hearing it, but I think it makes me a better person today."

Vaea is thankful for his cultural upbringing in Tonga. Now he's recovered from an injury many predicted would end his rugby career, he's also grateful for the perspective it has given him, too.

It was October 2012, preparing for his third season in Super Rugby, Vaea realised something was wrong with his calf muscle.

"My leg went white and I couldn't feel my foot, it was completely numb," Vaea recalls. "As soon as I took my boots off, the colour came back so we thought it was circulation."

Scans discovered blood-clots in his calf. Further examinations revealed the clots originated at his heart, which was damaged. Had it gone undetected, Vaea risked stroke and death.

Vaea was immediately put on blood-thinning medication and advised against any vigorous physical exercise that would rapidly elevate his heart-rate. Vaea and medics were optimistic of a six-month recovery, but the clots didn't clear.

"I did feel a lot of pressure, but not at the time I went in and the cardiologist said it was a six-month thing ... but after the first six months it was still dragging along, it passed two seasons, I was getting frustrated.

"I was wondering why me? How can it be me going through this? But I didn't blame anyone and I still believed in myself, I would come back and play footy.

"It was a lot tougher than a lot of people may think. This is the sport I love and to be out for two years, bang, almost it takes your whole career away. I realise how quick things can turn around.

"I was grateful the last two years to get to really know myself and see what people go through ... it makes me realise how lucky we are as athletes.

"I'm glad I have finally come out the other side of the tunnel and can see the light, it's a massive relief."

English is Vaea's second language, raised speaking Tongan.

Brumbies teammates call him Dox, given it's what they thought he was calling them when he arrived at the club years ago. He was actually saying Toko, Tongan slang for Tokoua, which means mate or brother.

Vaea considers the Brumbies family. Like his partner, Samantha, and step-son, Copper, 6, the Brumbies were a support he needed during his health battle.

Given medical clearance to resume rugby late last year, Vaea had signed a trial contract with French club Grenoble, but lasted just two weeks abroad before returning to Canberra on a supplementary contract with the Brumbies.

Vaea and the Brumbies were preparing to take a long-term approach to his comeback. But such was his physical improvement - losing 30kg in the pre-season - he was thrust back into Super Rugby for the season-opener against the Reds.

Before he knew it, Vaea was standing in the middle of his teammates again, leading the Brumbies victory song.

For someone who had been living in "slow motion" for two years, he admits he's still adapting again to the pace of professional football, on an off the field.

"I believe in myself, I didn't what to regret anything," Vaea says of his return from France. "I want to give [Super Rugby] one more crack and if I wasn't good enough then so be it.

"I was aiming for long-term, then all of a sudden this thing was going to happen and I had to fast-track everything.

"From someone who the last two years, just get out of bed, can't really do much … everything's going so fast at the moment.

"Singing the Brumbies song again, I felt home."

Early in his career, Vaea was compared to his childhood idol, former Australia Wallabies powerhouse Toutai Kefu, also of Tongan origin.

After his dominant performance against the Western Force last weekend, Brumbies coach Stephen Larkham predicted Vaea could still yet become a Wallabies great.

The Brumbies are negotiating to re-sign Vaea for another two years and hope to finalise a deal soon.

"I'm very grateful for Stephen believing in me, that I can still be the same footballer I was a couple of years ago before I got injured," Vaea says.

"It's everyone's goal in Australia to play for the Wallabies, but I don't want to be looking too far ahead. My job is to play good footy for the Brumbies. Hopefully we'll get to the final and win the Super Rugby.

"I feel like I'm not quite there yet, I'm still working on it, taking it step-by-step. I think I've got a lot more in me. I think the two years taken away from me can make my career go longer now. I had a two-year break, I'm fresh."