Sylvester Stallone tried to hide his agony over the loss of his son Sage behind dark glasses at the funeral.
The Hollywood star and his family gathered in Los Angeles to bury his eldest child, who died of a suspected overdose on July 13, the Sun reported.
Stallone was comforted by wife Jennifer Flavin and his brother Frank at the memorial service at St Martin of Tours Catholic Church.
Sage, 36, a film-maker and actor, appeared in ‘Rocky V’ alongside his dad.
He had been due to marry his girlfriend within months.
Coroner’s investigators are probing his death.
According to reports, as many as 50 empty pill bottles were found near his body at his Hollywood Hills apartment.