Kym, who plays Michelle Connor in the ITV soap, spoke about her 17-year-old daughter Emilie Cunliffe following her audition on The Voice UK.
"I got very angry on Twitter," said Kym. "Very angry indeed. People are entitled to their opinions - that's absolutely fine - and people can say what they want about me, I'm not bothered, but you can't attack a child, particularly about their appearance. It's disgusting.
"It's those kinds of people that add to the flames of eating disorders and things like that and it's really bad. They're so sick."
Emilie's audition was shown last Saturday but she was left in tears after none of the coaches turned their chairs around, meaning she didn't get through.
"It was a little while ago for her," said Kym. "She auditioned last year when she was 16 and she turned 17 in November.
"She really wanted to do it but she was so nervous, and she's used to singing in front of people - she sings a lot with me at charity events."
Despite the knockback, Kym said Emilie is still hoping to pursue a music career.
"It's all she wants to do," Kym continued. "It's her life. I wish she'd be a lawyer, or a doctor or something, but that's all she wants to do. It's in the blood!
"She was really uncomfortable with the song and the nerves just took over her and she was so disappointed with herself. She has her whole life ahead of her and I have no doubts."
Former Hear'Say singer Kym, added: "I'm going to support her because I would be a hypocrite if I didn't do that."
Kym, who got engaged to boyfriend Dan Hooper in December, was also on the topical panel show to talk about Corrie's upcoming bus crash storyline.
She said: "It's been a great storyline to be involved with and it's all linked with Steve's depression storyline, which has been fantastic to be involved with, and hopefully we've done that justice."
Reveal is now on Google Plus! Join us here for the latest pictures, fashion and celebrity news!
Watch Emilie's Voice UK audition below: