Watch South Yorkshire schoolgirl's sensational performance on The X Factor

Holly Tandy, from Barnsley, impressed Simon Cowell and the other judges with her cover of Alicia Keys’ If I Ain’t Got You on last night's show.

The judges were left shocked when Holly told them she was just 15-years-old.

The teenager was only able to audition after the age limit for this year's series was lowered.

Holly immediately impressed Simon by telling him how she ad once sung in front of an empty crowd after everyone walked out of one of her performances.

She credited her grandfather, who was a singer in a band during his youth, for inspiring her and being her number one fan.

After her audition ended, which saw Holly earn four yes votes from the panel, her grandfather could be seen wiping away his tears.