Nick Reiner, charged with murdering his parents, Rob and Michele Singer Reiner, spent much of his life battling drug addiction, an affliction that millions of Americans face.

© Constanza Hevia H. for The New York Times

Nick Reiner, charged with murdering his parents, Rob and Michele Singer Reiner, spent much of his life battling drug addiction, an affliction that millions of Americans face.

© Constanza Hevia H. for The New York Times

Neighbors said a pall had fallen over the wealthy Los Angeles area where Rob Reiner and his wife, Michele, were found stabbed to death.

© Mario Tama/Getty Images

After finding the slain couple, investigators focused on their younger son, Nick, as a suspect. He was formally charged with murder on Tuesday and appeared in court on Wednesday.

© Mario Tama/Getty Images