Sage Stallone's cause of death will not be known for up to two months.
The 36-year-old actor - the sun of Sylvester Stallone - was found unresponsive at his home in Studio City, Los Angeles, on Friday (13.07.12), and while his autopsy was completed yesterday (15.07.12), his cause of death is still unknown.
A spokesman for the Los Angeles County Coroner told CNN that it can take six weeks for toxicology tests to be completed.
Prescription drugs were reportedly found beside his body, and Assistant Chief Coroner Ed Winter has confirmed prescription bottles were uncovered in the investigation, but he has not revealed what they contained.
But Sage's attorney and longtime friend George Braunstein claims the actor didn't even drink or take drugs and believes his death was a ''tragic accident''.
He explained: ''I never knew him to drink alcohol. I never saw him take drugs. I never knew of anything like that at all.
''He didn't have a history of drug or alcohol abuse. We all think it was some sort of tragic accident.''
George also revealed Sage - who was rumoured to have been dead for three or four days before his body was found - posted pictures on his Facebook account 17 hours before his body was discovered, and he planned to tie the knot ''as early as next weekend'' in Las Vegas prior to his death.
He added: ''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.''
Sage was Sylvester's son from his first marriage to Sasha Czack, and the pair have both been left ''devastated'' by the news.
In a statement released through his representative, the 'Rocky' actor said: ''Sylvester Stallone 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.''