Melissa Armstrong, 21, was told she has a "nice sweet voice" by judge Tulisa Contostavlos, but was also urged to follow in Cole's footsteps by joining a girl group.
Asked if she told Cole she was auditioning, Armstrong told Heat: "No, I was too nervous. I didn't want to jinx it.
"I never auditioned before, when she was a judge, because I didn't want everyone to think it was biased. It would have been really weird auditioning for her."
She continued: "I got through two auditions with the producers before they found out Cheryl was my aunt.
"At the [filmed] audition they were prompting me to start taking about Cheryl. They asked us to sing Cheryl's songs a few times and I was dubious at first."
Armstrong added: "I didn't go on to be Cheryl. I think it could be manipulated on telly to make it look like I just want to be her.
"She'll know I didn't go on to copy her. I'm in the recording studio right now, but I think I might try and get in a girlband. I'm done with The X Factor - I hate queueing!"
