Rob and Nick Reiner were constantly "butting heads" on the set of their film Being Charlie! The 2015 film, which was written by Nick and directed by Rob, was very much inspired by the screenwriter's own history with drug addiction and homelessness, beginning when he was a teenager. (c) FayesVision/MEGA/WENN & Michele Singer Reiner/Instagram The father and son have claimed the experience of making the movie brought them "closer" than ever before. But it turns out things were quite tense on set! Following the news of Rob and his wife Michele's tragic death - for which Nick has been arrested - several actors on the project spoke out about the unusual behavior they witnessed. Related: Rob Reiner's Son Nick On Suicide Watch After Being Arrested Speaking to Page Six on Monday, stunt performer Erik Audé, whose scene was ultimately cut from the movie, claimed there was a ton of "tension" between the family members - making it really awkward for everyone else! Erik recalled arriving to set once and discovering the creatives were in the middle of an argument in front of the entire cast and crew! "They're just going off on each other. You could tell [Nick] was spoiled and Rob was just sick of his s**t." Erik recalled the "tension" in the room, adding: "I just assumed, whether this is correct or not, this kid must be pushing all his buttons. Rob can't do anything right. He's a nepo-baby, a spoiled kid to the tee." Erik's assessment went on: "Obviously he loved his son because he's doing this movie for his son, and still, his son was unappreciative." He added: "I picked up on all that hostility from just one day on set. That's how weird and awkward that exchange was." But things were uncomfortable even when Rob and Nick made amends. They calmed the waters with a "kiss on the lips." Erik reflected: "Families fight, but they do it in the privacy of their own home. People have a way of filtering themselves around other people. They didn't." From the moment Erik heard the heartbreaking news of Rob and Michele's deaths, the stunt guy felt the 32-year-old was at fault, telling DailyMail.com: "I said, 'I bet you anything it was his son.'" He elaborated: "They were fighting and arguing with each other while they were on set. They were kissing each other on the lips, which was weird. ... They were bickering and going off on each other on set. It wasn't comfortable. There was definitely hostility there." Erik recalled an incident when Nick was "sitting on a couch," and the director was "standing over the couch, and they were bickering back and forth," explaining: "The way couples would fight in front of people, they just don't care anymore about showing their dirty laundry, if that makes sense. That's the way the dad and the son worked." Hear more about Erik's experience: View this post on Instagram A post shared by Erik Audé (@erikaude1) A production source for Page Six reflected on the challenges of the film for the pair, claiming it didn't bring them closer like they tried to insist: "Making the movie was meant to be a healing process for them both, but from what I heard, it did the opposite, and didn't help their relationship at all. Working together on that project made their relationship worse, it seemed to increase the tension between them." Oof. Another actor, Nathan Stevens, told DM that The Princess Bride filmmaker "had his own way of doing things" on set versus his son, pointing out about Nick's working relationship with his famous dad: "I'm sure he probably had some frustrations." He continued: "There may have been some miscommunications - just his dad being the boss, Nick being his son and of course it is Nick's movie. There were probably some issues with that. I'd see Rob acting like he was frustrated with Nick." That said, Nick "was always kind" on set and noted that "he didn't seem like he was on drugs at that point." Nathan's brother, David Stevens, also an actor on the movie, felt Nick was "happy" to be working with his dad on the movie: "He was really proud of himself. He was really proud to be his dad's son. He was just a lovely, joyful filmmaker. ... [Being Charlie] was an attempt to continue repairing the relationship by doing something together." He furthered: "When a family has their demons - which a lot of families do, some more than others - but when a father and a son get the chance to, I don't know, exercise those demons, not just in the story of Being Charlie but that a father and son could reconcile as well by doing something special like that." Nick had a years-long battle with addiction and mental health struggles, with his mother reportedly telling friends the co-parents had reached a breaking point lately and didn't know how else to help their son. These kinds of challenges are so, so tough. It's clear the father and son had a complex relationship through it all... If you or someone you know is experiencing substance abuse, help is available. Consider checking out the resources SAMHSA provides at https