Sage Stallone, son of Sylvester Stallone, was found dead in his Los Angeles-area apartment on Friday.
The cause of death is undetermined at this time, however, authorities say there were no signs of foul play.
There were no signs of forced entry and no suicide note. But prescription drugs were found in the apartment.
"There are some prescription bottles, however I'm not going to detail what they are or how many," says LA County Assistant Ed Winter.
Sage had updated his Facebook account about 17 hours before he was found. His friend and lawyer, George Braunstein, says he didn't show any signs of drug use, depression and didn't even drink.
"We don't have any of the details. He wasn't depressed. He was thinking about getting married. He had his whole life ahead of him."
Sylvester Stallone's publicist says the actor is "devastated and grief-stricken over the sudden loss of his son."
"Sage was a very talented and wonderful young man," continues the publicist, Michelle Bega. "His loss will be felt forever."
Sage played Rocky Balboa's son in 1990's 'Rocky V'. The 36-year-old was Stallone's child with his first wife, actress Sasha Czack.
An autopsy will be performed to determine the actual cause of death.