Witnesses say that on the night before Rob Reiner and his wife Michele were brutally murdered, the couple had a public argument at comedian Conan O’Brien’s Christmas party with their son Nick, who is a suspect in their deaths.

Nick was arrested on suspicion of murdering his mother and father on Sunday and is being held on a $4 million bail.

The Reiners were reportedly attending the party at the former TV host’s home where witnesses have said that Nick was “acting strangely,” according to the L.A. Times.

Another source told People magazine that the This is Spinal Tap director and his son were arguing over money.

“Rob wouldn’t agree to give him the money because he knows his son has a serious drug addiction and was lying about it,” the source claimed. “Rob was saying no, and they got in a big fight.”

Another source said that, “Nick was freaking everyone out, acting crazy, kept asking people if they were famous.”

Other sources told TMZ that the director’s wife was lamenting to friends that Nick had been returning to substance abuse and they were at wit’s end on what to do about it. “We’ve tried everything,” Michele reportedly told friends.

The Reiners left the party immediately after the argument, witnesses said.

Rob Reiner and his wife, Michele Singer, were found murdered in their Brentwood home less than a day later.

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