The singer/actress was due to record a home visit with contestants in Los Angeles earlier this week (begs24Jun13), but cancelled her appearance a day before filming.
A spokesperson for the show tells the Sydney Daily Telegraph, "It was a shame Miley couldn't record with us but she did pick up the phone and help us find our new guest judge. We're thrilled with our new guest judge, they will be a great asset to the show."
The representative did not confirm who Cyrus put forward as her replacement, but reality Tv star Kelly Osbourne has hinted she stepped into her pal's role.
In a public Twitter.com message to the former Hannah Montana star, Osbourne wrote, "Called U (you) but no answer I hope you are sleeping & getting better dont worry I'm filling in for you today everything got sorted!"
Cyrus has been sharing updates about her condition with her followers, tweeting, "Can't move my neck. Can't breathe. Can't barely speak (sic)... Sick in bed. Neck, belly, throat, head..... It all hurts."