Cooper Koch’s Brother Says the Actor ‘Stands With’ Erik and Lyle Menendez After ‘Monsters’ Backlash

Cooper Koch's brother reassured fans that the actor sympathizes with Erik Menéndez — despite how Netflix's controversial Monsters series presents the infamous murder case.

Payton Koch shared photos on Thursday, September 19, of Cooper, 28, on set, writing via Instagram, "Have never felt more proud of another human being. I love you so much and am so so happy for you."

In response, some fans took to the comments section to express their issues with the series since Cooper doesn't have public social media accounts. One person specifically questioned how Netflix portrayed Erik, 53, and Lyle Menéndez.

"The audacity of Cooper to have photos of Erik everywhere on the mirror like a shrine when he’s participating in a show that drags his name through the mud," read the comment. "Does anyone in this show not have any morals? We, in the Menendez Supporters community and the abuse survivors community, are horrified by this show. Completely horrified."

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Payton reassured those frustrated by Monsters that Cooper approached the material with respect for the Menéndez brothers.

"Hi! I won’t speak for cooper, but I will say that he cares immensely for the boys and stands with them and all victims of abuse," Payton wrote before referencing Cooper's single-take monologue episode. "He did everything he could to ensure their stories of abuse were seen on screen and I think in episode 5, it is abundantly clear where he stands. Actors are only vessels for the writers/producers of the show."

Monsters, which premiered on Thursday, centers around Lyle (Nicholas Alexander Chavez) and Erik (Koch), who were convicted for the 1989 murder of their parents, José (Javier Bardem) and Kitty (Chlo? Sevigny). The show initially explores the brothers' perspective about how José and Kitty's alleged physical, emotional and sexual abuse led to them killing their parents. The second half of the season, however, turns the narrative around and raises questions about whether Lyle, 56, and Erik's claims were false.

"Any true story portrayal is going to be tough, but please trust me when I say he does care about them and their story. ?????," Payton continued. "I totally understand and hear you. I’m glad you were able to see Erik in episode 5 and I can only hope that people’s perspectives are shifted to sympathize with the boys, even though the last few episodes do not portray them in the best light. Thank you for sharing and know you are not alone in the way you feel ????."

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Payton's insight comes after Variety confirmed that Cooper visited the Richard J. Donovan Correctional facility with Kim Kardashian on Saturday, September 21, to give a talk about prison reform to inmates, including Lyle and Erik.

Erik, meanwhile, spoke out about Monsters one day after it was released.

“I believed we had moved beyond the lies and ruinous character portrayals of Lyle, creating a caricature of Lyle rooted in horrible and blatant likes rampant in the show,” read a statement from Erik that was shared via Lyle’s Facebook page. “I can only believe they were done so on purpose. It is with a heavy heart that I say, I believe Ryan Murphy cannot be this naive and inaccurate about the facts of our lives so as to do this without bad intent."

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Erik wasn't thrilled to hear how he and Lyle were characterized, adding, “It is sad for me to know that Netflix’s dishonest portrayal of the tragedies surrounding our crime have taken the painful truths several steps backward — back through time to an era when the prosecution built a narrative on a belief system that males were not sexually abused, and that males experienced rape trauma differently than women. Those awful lies have been disrupted and exposed by countless brave victims over the last two decades who have broken through their personal shame and bravely spoken out.”

He continued: “So now Murphy shapes his horrible narrative through vile and appalling character portrayals of Lyle and of me and disheartening slander. Is the truth not enough?”

Monsters is currently streaming on Netflix.