Ke$ha has "zero tolerance" for bullying because her brother has endured years of taunting over his stutter.

The TiK ToK hitmaker has witnessed the effects of bullying firsthand - her 13-year-old sibling Louis has been targeted because he has a stammer.

"I used it to motivate me then, and I still do. I remember every person who told me I couldn't do something or that I was ugly or too fat."

She tells Seventeen magazine, "I'm all about standing up to gay/lesbian/transgender bullying, but it's also about my little brother. He's 13 and he gets made fun of because he has a stutter. I just have zero tolerance for people making fun of others".

The singer, real name Kesha Rose Sebert, admits she has also endured years of verbal abuse, but she uses insults and negativity to fuel her success.

She adds, "I used it to motivate me then, and I still do. I remember every person who told me I couldn't do something or that I was ugly or too fat. I have a 's**t list' - people from my past who have been soulless and judgmental.

"Even after I got through my awkward phase, got my braces off, and figured out how to dress my body, people in the music business were like, 'You're never going to make it.' I see them now and I'm like, 'Ha!' That's one of the reasons I named my (latest) record Warrior.

"You can be a victim and let that eat your soul, or you can say, 'You're going on my list and I'm going to prove you wrong!'"