Hollywood film director Rob Reiner and his wife Michele Singer Reiner were found dead in their Los Angeles home on Sunday (14 December).
The pair are reported to have been found with stab wounds, although their official cause of death is yet to be revealed.
A spokesman for the Reiner family previously confirmed the death of Rob, who directed several box-office smashes, including This Is Spinal Tap, Misery, When Harry Met Sally and The Bucket List, and his wife of more than 35 years, photographer and actress Michele.
They said in a statement: "It is with profound sorrow that we announce the tragic passing of Michele and Rob Reiner. We are heartbroken by this sudden loss, and we ask for privacy during this unbelievably difficult time."
Nick Reiner, the couple's 32-year-old son, was arrested that same night, and it was reported he was being held without bail after being 'booked for murder'.
Then, on Tuesday (16 December), the news broke that he had been charged with two counts of first-degree murder after the killing of his parents.
Los Angeles district attorney Nathan Hochman said no decision had been made on whether to seek the death penalty in the case, but they will take the 'thoughts and desires of the family into consideration'.
Nick Reiner has been charged with two counts of first-degree murder after the killing of his parents, Rob Reiner and Michele Singer Reiner (Laura Cavanaugh/FilmMagic / Getty Images) "Their loss is beyond tragic, and we will commit ourselves to bringing their murderer to justice," Hochman said.
He added: "Prosecuting these cases involving family members are some of the most challenging and most heart-wrenching cases that this office faces because of the intimate and often brutal nature of the crimes involved."
Screenwriter Nick has not entered a plea and did not appear in court on Tuesday as expected because of unspecified health reasons, according to his lawyer, Alan Jackson, who said
said his client was not medically cleared.
Tributes have poured in for the murdered Hollywood filmmaker (David Livingston / Contributor / Getty Images) Jackson did not specify what medical issue prevented Nick from being cleared, saying only that it was 'procedural'.
He is expected to appear before a judge on Wednesday (17 December).
Nick has a history of addiction struggles, which reportedly began when he was a teenager.
He co-wrote the 2016 film Being Charlie, which his father Rob directed. The film explored addiction and recovery, and Nick has spoken openly in the past about his own struggles with substance abuse.
Nick did not appear in court on Tuesday (16 December) (Michael Buckner / Contributor / Getty Images) Speaking to PEOPLE back in 2016, he revealed he had been in and out of rehab for addiction treatment that started when he was 15. He also told the outlet that he spent weeks sleeping on the streets.
"Now, I’ve been home for a really long time, and I’ve sort of gotten acclimated back to being in LA and being around my family," he shared at the time.
Rob and Michele also share two more children together - Romy, 28, and Jake, 34. Rob was also previously married to actor-director Penny Marshall from 1971 to 1981 and adopted her daughter, Tracy Reiner, 61.