Detectives are now piecing together the final days of Reiner’s life and his turbulent relationship with his son.
Nick, who had struggled with addiction for years, was said to have been living in a guest house at his parents’ $13.5m (£10.1m) home.
Family friends told of how Michele, a producer and actress, had become increasingly concerned about his mental health in recent weeks.
In the grip of drugs, Nick had distanced himself from his family. But having returned to his parents’ home in Los Angeles, he frightened them with lengthy, chaotic binges, an insider told the Daily Mail.
“He would do meth and not sleep for days and then have outbursts, breaking things, punching walls,” the source said, claiming that Rob and Michele had threatened to kick him out of the house if he did not stop using drugs.
In September, the family appeared united as they posed alongside Nick, their daughter Romy, their elder son Jake and his wife, Maria Gilfillan, at the premiere for Spinal Tap II.
