The 36-year-old was found dead on Friday at his home in Hollywood, with rumours circulating of possible suicide or a drug overdose "accident". He may have been dead for as long as a week before allegedly being found by his housekeeper. Depression and prescription drugs have been mooted. There were no signs of foul play or trauma, or a suicide note, confirms Ed Winter of the LA Coroner's office.

An autopsy has been completed on Rambo-star Sylvester Stallone's son and the slow wait for toxicology reports has begun - a full analysis is expected to take two months. Now all eyes, and rumour mills, turn to the Studio City-based actor's private life and what may have led a man who apparently had it all, to die so young.

It is a sad picture of Hollywood's darker side that one of the photographs circulating since the death is that of the coroner's van carrying Sage's body as it passes an open-topped tourist bus, its passengers holding cameras aloft. With conflicting stories abounding, those unwitting tourists are likely to know as much as even some "inside sources".

The actor, who had 13 movie credits to his name, is said to have been "out of it" and living in a state of semi-squalor in the months before his death.

According to TMZ, a May photoshoot at Sage's home was a fraught affair, with Robert Rhine, editor-in-chief of Girls and Corpses magazine, a comedy horror publication, alleging that Sage was "on something".

Rhine told the site that he waited 45 minutes for the door to be answered and that the actor was slurring and stumbling.

In line with some reports of the actor and filmmaker's lifestyle of late, Rhine went on: "What’s troubling is the fact that the people around him claim there were no signs. I saw the signs. When everyone from the shoot heard the news, none of us were surprised."

Sage is said to have "lived like Howard Hughes" in a home that was "disgusting", one law enforcement source told the site. His room was reportedly littered with beer and soft drink cans, food and cigarette butts.

According to RadarOnline, Sage may have used prescription drugs. "There were a number of prescription bottles found at the scene but it did not appear to be suicide and no note was found," a source said.

But, contradicting reports of a troubled home life, the actor is said by others to have been at a happy, healthy stage of life.

George Braunstein, longtime friend and attorney to Sage, told E! "He was very creative, energetic and very full of life. We were just joking about how he was going to get married and have a fun marriage.

"There was nothing dark or depressing, no problems, certainly no financial problems."

He said he was not aware that Sage had drug or alcohol problems.

"Never, no, not from the day I met him... I never knew him to drink alcohol. I never saw him take drugs. I never knew of anything like that at all," he told the network.

"I'm going to wait to see what the coroner says. I think it was either natural causes or a terrible accident. I don't think it had anything to do with drugs, he wasn't that kind of guy. He wasn't anyone trying to take his life."

He echoed his words to People, explaining that "Sage didn't even drink. There was a report that his room was filled with liquor bottles. Actually, they were empty bottles of Dr. Brown's Cream Soda."

A wedding in Las Vegas is said to have been planned for the very near future, even as soon as next week, according to some reports, though no confirmation has been made of the fiancée's identity. It would have been his second marriage, with a 2007 marriage to Starlin Wright annulled in 2008.

Sylvester Stallone is said to be a "wreck" after hearing the news of his son's death at Comic Con in San Diego. According to MailOnline, the 66-year-old Hollywood stalwart "was shocked, short of breath and almost collapsed. He just went quiet before sobbing uncontrollably. He is a wreck at the moment," a source told the site.

He was pictured at the event with close friend and co-actor Arnold Schwarzenegger, who later released a statement: "My thoughts and prayers are with Sly and his family. Sly has become a great friend over the past couple decades, and I know how important his children are to him.

"I want him to know that my family and I, and his fans all over the world, support him during this difficult time."

The eldest son of the action hero, Sage was no spotlight dweller - a reclusive teen, he spent much time watching zombie horror films and is said to have had a strained relationship with his father, at one stage "screaming", he told People magazine in 1996: ""You never spent time with me! You never spent time with my mother!" - that was true, I was looking into my father's face and really saying that."

But, as difficult as the father-son relationship may at times have been, it was Sage's role alongside his father Sylvester for which he is perhaps best-known, carried, in part, by the juggernaut that is the Rocky series. The young Sage, aged just 13, played the part of Rocky Balboa Jr in the 1990 installment, Rocky V. It was his film debut.

The father-son duo again acted together for the 1996 Manhattan disaster film, Daylight, alongside Viggo Mortensen and Amy Brenneman. Sage went on to have roles in 11 other productions, the most recent of which was 2010 short film, The Agent.

Sage and brother Seargeoh, 32, are sons from the actor's 11-year marriage to Sasha Czack. The first of three marriages, Stallone and Czack split in 1985, with Stallone going on to marry Brigitte Nielsen and then Jennifer Flavin, with whom Stallone has three daughters, Sophia, Sistine and Scarlet, half-sisters to Sage.

Czack is "devastated", Braunstein told E! News. "They're trying to sort everything out and plan a funeral. Sylvester called, he's upset too. They may be celebs, but they're regular parents. It's tragic."

Sylvester Stallone's representative, Michelle Bega, told TMZ that the star "is devastated and grief-stricken over the sudden loss of his son Sage Stallone.  His compassion and thoughts are with Sage's mother, Sasha.  Sage was a very talented and wonderful young man.  His loss will be felt forever."

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