Sylvester Stallone's son, Sage Stallone, died from a heart attack, according to findings by the Los Angeles County Coroner and obtained by TMZ.
Sylvester Stallone speaks out on son's death: "It's very, very tough"
Although Stallone was only 36, there was evidence of heart disease, and it was determined that his death was from natural causes.
Stallone was found dead on July 13. He starred alongside his father in Rocky V and Daylight and later became a director and producer.