Sylvester Stallone was spotted having a somber dinner at Craig’s on Melrose in LA on Thursday, the same day his late son Sage’s autopsy report was released saying he died of a heart attack. “Photographers were outside waiting for Sly,” says a source. “He left through the kitchen. He seemed in a somber mood and like he was trying to have a meal unnoticed. That definitely didn’t go well.” Sage was found dead in his home on July 13. Stallone was hit with more tragedy this month when his half-sister Toni-Ann Filiti died of cancer.