Sebert, who also claims Luke's behaviour "almost destroyed us", was by her daughter's side in court in February as Kesha attempted to free herself from a Sony contract, which she claimed tied her to Luke, real name Lukasz Gottwald.
The producer denies raping Kesha and has accused the singer of lying under oath as she pursues a lawsuit against him.
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In a series of tweets last month, he wrote: "I didn't rape Kesha and I have never had sex with her. Kesha and I were friends for many years and she was like my little sister."
Dr Luke filed a countersuit against Kesha and her mum for defamation and extortion, alleging the mother-daughter duo threatened to go public with sexual assault claims unless he released her from the management contract the star, who is now 28 years old, signed with him when she was 18.
"Kesha and I made a lot of songs together and it was often good but there were creative differences at times."
Dr Luke has also insisted that claims Kesha has made about recording restrictions, under the terms of her Sony contract, are false, insisting she's still free to work with whoever she pleases, but in the Billboard piece, Pebe states, "Kesha's allowed to work with another producer, but Luke gets to approve them. He gets to approve of anyone she works with. He has final say over everything."
- WENN