Chaz Bono 'Frustrated' by Some of Caitlyn Jenner's Critics

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Chaz Bono paved the way for Caitlyn Jenner, documenting his gender transition in 2011 Emmy-nominated documentary Becoming Chaz. ET sat down with Chaz, who had strong words for some of Caitlyn's critics.

"It's a difficult thing and it's frustrating that people would think that somebody would do this for publicity, or for any other reason than because you have to do this," Chaz told ET.

Chaz has been getting positive publicity for his dramatic role as a murderer in the play Down the Road, currently at the Lounge Theatre in Los Angeles, especially from his famous mother Cher.

WATCH: Chaz Bono Reveals Diet Success

"She actually does make me nervous, unfortunately, in the audience," Chaz said. "I will be honest on that. She does. She is a tough critic, and she doesn't pull punches. The last play I did she didn't like."

Fortunately Cher is a huge fan of Chaz's new project, thanks to the hard work and preparation he put into the role.

"I did a lot of research into serial killers, but the thing that kind of helped me the most was a couple books by researchers on psychopaths," Chaz said.

Watch the video for more.