Sylvester Stallone is mourning the death of his son Sage Stallone who worked with his father on Rocky V playing the protagonist's son.
The New York Post report the 36-year actor, writer and producer was found dead at his Hollywood apartment yesterday.
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Sources informed the paper that Sage passed away following a drugs overdose but coroner's officials are investigating whether it was accidental or suicide.
Police discovered Stallone's son when responding to a 'welfare check' after concerned friends alerted them — he was found by his housekeeper and paramedics announced him dead at the scene
Sylvester's spokesperson confirmed the news saying the actor is 'devastated' and 'grief stricken' over the sudden loss of his eldest son.
She said: "His compassion and thoughts are with Sage's mother, Sasha.
"He was a very talented and wonderful young man. His loss will be felt forever."
Sage was the elder of two boys Sylvester had with his ex wife Sasha Czack although he leaves behind three half sisters.
The actor's lawyer also spoke on behalf of the star expressing his shock over Sage's death:
"He was in good spirits, and working on all kinds of projects.
"He was planning on getting married. I am just devastated. He was an extremely wonderful, loving guy. This is a tragedy."