According to The Mirror, Cheryl has been poorly all week as she fights a fever and a throat infection, meaning the 31-year-old has been keeping in touch with act Lauren Platt by phone.
She took to Twitter to explain her absence to fans, writing: "Sorry for my absence on here the past few days. I have been so sick. Trying to be better for sat."
Speaking about tonight’s live show, a show source told The Sun: "There's a real chance she'll miss it."
The remaining X Factor acts will take on Elton John and Whitney Houston songs as they battle it out onstage.
Cheryl’s act Lauren Platt, 17, will attempt to impress her mentor’s fellow judges with a Whitney track.
Tune in tonight at 8pm on ITV. Check out our live commentary on Twitter: @CloserOnline.
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