Aziz Sergeyevich Shavershian, 22, who was known as "Zyzz" to his legion of online fans, died on Friday after suffering a heart attack in a Bangkok sauna.

His mother, Maria Shavershian, said a post-mortem examination revealed that her youngest son suffered from an undiagnosed heart condition, which triggered cardiac arrest.

"I am shattered, we are doing very bad," Mrs Shavershian said.

The family, who are intensely private, were given the news only on Monday, three days after Mr Shavershian's death.

They have not yet made plans for his funeral but say it will be a private ceremony for family and close friends. They are expecting to receive his body this weekend.

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Mr Shavershian, from Carlingford, was a fulltime business and commerce student who crafted the wildly popular online "Zyzz" persona after discovering bodybuilding in his late teens.

He released a book, began promoting bodybuilding supplements and made countless videos in character as "Zyzz"; an aggressive and flamboyant, heavily-tanned showman. Throughout his studies he also worked part-time as a stripper with the male revue Sydney Hotshots.

Mr Shavershian's fame was contained to the bodybuilding world until two weeks ago, when The Sun-Herald wrote about the arrest of his older brother, Said, 25.

He was found in possession of an anabolic steroid and pleaded guilty to the charge last week. Said Shavershian, a personal trainer at Fitness First, was fined $479.

The younger sibling was not pleased with his inclusion in the article, which raised questions about the extent of steroid use in amateur bodybuilding and to what lengths young men were going to emulate their idols.

"The article potrays me in a negative light, using my photo for what was an article predominately [sic] about anabolic steroids when I have never been charged, caught, or convicted with anything related to drug use," he said in an email.

"What I have done, however, is use the internet to build up my name and brand, I have my own protein label and supplement sponserships, all made possible through social media.

"As you may be able to tell from my articulacy, im no idiot, Im a student studying business management at university and essentially have been successful im marketing myself - i have around 52000 facebook followers; that's only a few thousand short of Kyle and Jackie O's Facebook support group."

That following has swelled to more than 73,000 since news of his death broke online late on Monday.

Said Shavershian posted the following message on his brother's private Facebook profile: "Rip brother, I love you sooo much. It wasn't sposed to end like this :( I can't stop Fkn crying I'm dyeing on the inside. I will see you soon. You weren't just my brother... You were my best friend too. Miss you soo much I just hope I wake up tomorrow and this is all a bad dream."

A spokesman for Sydney Hotshots, Aziz's employer for three years, said he was struggling to come to terms with the news.

"He was supposed to be back this week; I had a few jobs lined up for him next week," the spokesman said.

"He was a great guy. The YouTube [video] stuff was all for show. Aside from the steroids, he was a lovely guy."

Further tributes flowed on Aziz's private Facebook profile and online bodybuilding forums, where he has been hailed as a god.

"You were the motivation for me and others to acquire aesthetics...," one friend said.

Another friend wrote: "RIP Az! U were 2 real inspiration 2 all. U will b missed by all. Really sad 2 loose such a young life, I stil cant belive it :((((."

A separate Facebook page was set up on Tuesday. One fan wrote: "Zyzz changed my life, I've never met him. But, when my life was hard and i felt like there was nowhere left to go, Zyzz showed me a new world, showed me that we are what we put into life, and that you can change yourself into whatever you wish to be."

When contacted by the Herald this morning, Said Shavershian said his family asked for privacy.

"At this stage it's a no comment," he said.

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