Sage Stallone's attorney said the 36-year-old son of Sylvester Stallone "never had any serious health problems" or had "a history of drug or alcohol abuse."
"Sage was a really young, very sensitive, and very talented kid," attorney George Braunstein told People magazine. "There has been no indication that there was anything wrong in his life."
Sage Stallone was found dead Friday in his Los Angeles apartment by authorities and a housekeeper.
Authorities said there were no signs of foul play and his cause of death remains undetermined. An autopsy will be conducted in the next several days.
"There had been no personal contact with the deceased in the last few days," Los Angeles Police Department Sgt. Jim Parker said.
Authorities said there were no signs of forced entry and no suicide note, but there were prescription drugs found.
"There are some prescription bottles, however I'm not going to detail what they are or how many," Winter said.
Although media reports surfaced this weekend claiming that Sage Stallone may have been dead several days before authorities discovered his body, Braunstein told People magazine that he updated his Facebook account about 17 hours before he was found.
Braunstein said Sage Stallone was a creative genius.
"He had a lot of bright things on the horizon. He was talking about pictures he wanted to direct and write and ideas that he wanted to go forward with," Braunstein said.
Sage Stallone played Rocky Balboa's son in "Rocky 5" in 1990 and appeared in the film "Daylight" with his father. He also directed the 2006 short film "Vic."
"He was so private, we don't know a lot of the circumstances, even around his personal life. This was not someone anyone followed. This is someone that sadly a lot of people had forgotten about," said Ian Drew, senior editor with Us Weekly.
On Friday, Sylvester Stallone's publicist Michelle Bega told The Associated Press that the actor is "devastated and grief-stricken over the sudden loss of his son."
"His compassion and thoughts are with Sage's mother, Sasha," Bega said in a statement.
ABC News Radio and The Associated Press contributed to this report.