The family announced the death in a statement Sunday night expressing their grief.
"Today our beloved mum Julie passed away. Anyone who had met her would know what a truly special and kind lady she was. We are heartbroken and will miss her terribly, but she is now at peace."
Tony Cowell, one of her four boys posted a tweet to honor his mother, who died of a stroke.
"Very sad night tonight," he said. "We will all miss Mum so very much. She was the heart and soul of our family x."
Due to her death, the U.K. edition of "The X Factor" is canceling its Manchester auditions, the BBC reported.
A spokesman for Syco Entertainment, the music production company that also produces the popular singing competition, confirmed the cancellation saying: "[Auditions] were due to start today (Sunday) and carry on into Tuesday and Wednesday. Today's have been cancelled and we have not made any decisions beyond that."
The family was grateful for the decision.
"We would like to thank the media for kindly respecting Julie's privacy throughout and we politely request continued privacy for the entire family at this particularly difficult time," the statement said.
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