Sylvester and Sage Stallone Credit: Willi Schneider/Rex

Sylvester Stallone is in mourning.

Days after his son Sage was found dead at age 36, the 66-year-old superstar released a new statement to TMZ -- asking for privacy and respect as he grieves the loss of his eldest child, whose mother is his first wife Sasha Czak.

"When a parent loses a child there is no greater pain," the Rocky star says of Sage, a filmmaker and actor. "Therefore I am imploring people to respect my talented son's memory and feel compassion for his loving mother Sasha."

He adds: "This agonizing loss will be felt for the rest of our lives. "Sage was our first child and the center of our universe and I am humbly begging for all to have my son's memory and soul left in peace."

Similarly, Sage's attorney and friend George Braunstein suggested that speculation that his late friend abused prescription drugs or was unhappy before he died is off the mark.

"[He] was in good health, great spirits," Braunstein told NBC Los Angeles. He was thinking of getting married, working on a lot of film projects."