Jan. 7 (UPI) — Nick Reiner, son of slain actor and filmmaker Rob Reiner and his wife, Michele Singer Reiner, is scheduled to be arraigned on Wednesday for the alleged murder of his parents.

Reiner faces two counts of first-degree murder with a special circumstance of multiple murders and use of a dangerous and deadly weapon.

The arraignment is set for 8:30 a.m. PST at the Los Angeles Superior Court Stanley Mosk Courthouse.

Rob Reiner and Michele Singer Reiner were found stabbed to death in their Los Angeles home on Dec. 14, and police arrested and charged their son Nick, 32, the following day. He appeared in court on Dec. 17, but wasn’t required to enter a plea. He’s expected to enter a plea at his appearance Wednesday.

ABC News reported that police and Reiner’s defense attorneys are trying to piece together his psychiatric and substance abuse history. California law allows defense attorneys to signal as early as the arraignment whether they will use mental health in their defense.

A jury could find a defendant not guilty by reason of insanity, confining them to a psychiatric hospital instead of prison. But attorneys must show that the accused suffered from mental illness before developing an addiction. Mental illness caused by addiction doesn’t meet the legal standard, ABC reported.

After Nick Reiner’s first court appearance, his lawyer, Alan Jackson, said, “Our hearts go out to the entire Reiner family. There are very, very complex and serious issues that are associated with this case.

“We ask that during this process, you allow the system to move forward in the way that it was designed to move forward, not with a rush to judgment, not with jumping to conclusions, but with restraint and with dignity and with the respect that this system and this process deserves and that the family deserves,” USA Today reported he said.

The Bronx, N.Y., native — whose credits include All in the Family, This Is Spinal Tap, The Princess Bride, Stand by Me, Misery, A Few Good Men, When Harry Met Sally and Sleepless in Seattle — was 78. Michele Reiner was 70. Their children, Romy and Jake, are planning a memorial service for a later date.

Rob Reiner also adopted actress Tracy Reiner, daughter of his first wife, actress Penny Marshall.

Rob Reiner was the son of comedian and actor Carl Reiner, who had worked with Norman Lear and Mel Brooks, among others.

“The horrific and devastating loss of our parents, Rob and Michele Reiner, is something that no one should ever experience. They weren’t just our parents; they were our best friends,” Romy and Jake Reiner said the day after their deaths.