Rob and Michele Reiner were issued chilling warning over son Nick living at home before brutal murders

Rob and Michele Reiner were warned about letting their son live at their home after his medication was switched, potentially causing 'erratic' behavior, it has been claimed.

Nick Reiner, 32, appeared in court last week, where his lawyer entered a plea of not guilty to the murder of his parents two months after they were found stabbed to death in their $13.5 million Brentwood home on December 14.

It had been reported previously that the son of the Hollywood legend - whose siblings are no longer paying for his criminal defense - had suffered from schizophrenia and been open about his past with drug addiction. 

Now, it has been alleged that Nick had fired his psychiatrist and changed medications shortly before his parents were brutally murdered.

'The medical staff warned Rob and Michele not to let Nick live at home until he got his medication straightened out,' a source told Us Weekly.

A second source told the publication that the parents were trying to help their son figure out his prescribed drugs as 'they weren't working anymore.'

The insider said that the family's medical staff had 'warned Rob and Michele not to allow Nick to stay at their home due to the meds being switched, and [said] that it could make him exhibit even more erratic behavior.' 

Last week, it was revealed that Nick's siblings are no longer paying for his criminal defense as he faces murder charges for allegedly killing his parents, which he pleaded not guilty to.

Hours after the killings, he was arrested and has been held without bail.

But as the case moves forward, with prosecutors confirming it is eligible for the death penalty, his legal representation now rests with a court-appointed public defender.

TMZ reported that sources connected to Romy and Jake Reiner said there was no plan to hire another private criminal defense attorney. 

The outlet previously reported that prominent defense attorney Alan Jackson had been retained shortly after the murders but later withdrew from the case due to an undisclosed disagreement.

A public defender was appointed last month. At the time, it appeared to be a temporary measure. However, on Monday, Deputy Public Defender Kimberly Greene appeared in court and entered a not guilty plea on Nick's behalf.

One source told TMZ of his siblings, 'Nick's defense is Nick's defense. They're not involved.' 

The outlet reported that Jake and Romy have no plans to bring in private counsel and will no longer pay for his defense.

It remains unclear whether the siblings will weigh in on whether prosecutors should pursue capital punishment.

The 32-year-old looked gaunt and hollow-eyed as he sat hunched over in court in Los Angeles, California, on February 23, wearing brown prison garb. 

Nick was heard faintly whispering 'yes' when asked if he understood the proceedings during his appearance, which marked the first time he had been seen in custody. 

His head was shaved as he looked into the crowded courtroom, as if searching for someone he knew. 

At one point, an unidentified elderly woman waved at him, and Nick mouthed 'hi' to her and the older man sitting next to her.

This was his third court appearance after he was arrested following his parents' gruesome murders. It was the first time Judge Theresa McGonigle allowed him to be photographed in custody. 

The death penalty is still on the table for Nick, Los Angeles County District Attorney Nathan Hochman said.

Shortly after the three-minute hearing, Hochman addressed reporters outside the Downtown LA courtroom.

'The case is on track. We have provided the bulk of discovery to defense counsel and we are now waiting for the coroner's report. That will be provided to the District Attorney's Office and we will ensure that it will be provided to defense counsel.

'This case is a death penalty eligible case. Along those lines, we take the process in which we determine whether or not the death penalty should be sought extremely seriously. That goes through a very rigorous process.

'We will be looking at all mitigating and aggravating circumstances, and we have invited defense counsel to present to us both in writing and in a pleading, any arguments they would like to make in consideration going forward or not going forward with the death penalty. So that is an ongoing process.'

He is due to appear in court again on April 29. 

Nick has long dealt with mental health issues, as it was previously claimed that he had been placed in a mental health conservatorship five years before allegedly murdering his parents. 

He is believed to have switched his schizophrenia medication about a month before his parents were found dead by his sister, Romy.

Nick's latest court appearance comes just days after comedian Conan O'Brien broke his silence on the Reiners' deaths. 

Just hours before Rob and Michele were found, the filmmaker was seen clashing with Nick at O'Brien's holiday party.   

'It's just so awful,' O'Brien, 62, said in an interview with The New Yorker on Friday.

'I knew Rob and Michele, and then increasingly got closer and closer to them,' he said, adding that he and his wife, Liza Powel O'Brien, 'were seeing them a lot.' 

'They were just such lovely people. And to have that experience of saying goodnight to somebody and having them leave and then find out the next day that they're gone. I think I was in shock for quite a while afterward. I mean, there's no other word for it.

'And I think about how Rob felt about things that are happening in the country, how involved he was, how much he put himself out there — and to have that voice go quiet in an instant is still hard for me to comprehend,' O'Brien added.

It was reported that all three Reiners attended O'Brien's December 13 holiday party, where the filmmaker and his son were involved in a 'very loud argument.' 

It was also recently claimed that Nick is 'not competent to stand trial right now.' 

TMZ executive producer Harvey Levin told Fox & Friends last week: 'He is almost childlike in jail, we're told. 

'He can't process the consequences of what he's done. He knows what he did.

'He just can't understand where he is right now, and I know that sounds crazy, but he is out of his head right now,' Levin added. 

Levin said that the killings were 'incredibly brutal'. 'We know people in the medical examiner's office who are traumatized just by the pictures,' he said.

The TMZ producer added that the killings had 'all the markings of a meth murder' and that Nick had been using the hard drug at the time.

Prior to his hearing, a legal expert predicted that Nick's lawyer might build a public defense based on insanity. 

'One reason to roll out a mental defense now is that, by waiting, it can undermine the credibility of an argument later, causing people to ask, 'If he's so bad off mentally, why didn't you raise the issue earlier?'' lawyer Royal Oakes told the New York Post. 

Oakes said Nick's legal team might introduce the potential mental health strategy later on, now that he has entered a plea of not guilty.