Michael Keaton paid tribute to his nephew, who died of an accidental drug overdose, in his SAG Awards acceptance speech on Sunday.
The star came on stage at the Barker Hangar in Santa Monica, California, comically, by rolling on to it and apologising for his lateness due to a trip to the "men's room".
However, he then got serious when accepting his prize for Outstanding Performance by a Male Actor in a Miniseries or Television Movie for drugs drama Dopesick by outlining actors' duty to highlight societal ills.
"There is a massive inequity in the world," he repeated multiple times, noting how fortunate he is to be able to make a good living as an actor and be "part of a production like Dopesick that can spawn thought, conversation, actual change".
The show earned huge plaudits for its depiction of the origins of America's opioid epidemic and the role of the Sackler family and their firm Purdue Pharma in prescribing the dangerous painkiller OxyContin to millions of Americans.
"I can feel right now the rolling thunder of eye-rolling coming across, people saying to me things like 'Shut up and dribble', 'Shut up and act'," Keaton said, referring to right-wing commentator Laura Ingraham's criticism of LeBron James' political statements.
"The acting, I'll quit. The shutting-up, not so much," the actor added, to applause.
After praising Ukraine's President Volodymyr Zelenskyy, who has won plaudits for his bravery in standing up to Russian President Vladimir Putin's invasion of his country, Keaton got personal in addressing his own family's loss.
"Given the subject matter," he said of Dopesick, "this is for my nephew Michael and my sister Pam. I lost Michael, and it hurts."
His nephew died in 2016 following an accidental overdose of heroin and fentanyl. Keaton has previously said that his death influenced his decision to play Dr. Samuel Finnix in Dopesick, an adaptation of Beth Macy's book of the same name.
