YouTube superstar Susan Boyle canceled a second concert performance Thursday in Liverpool, England, on the Britain's Got Talent tour. Boyle denied a report in London's Daily Mirror that she has an hysterical fit over Pebbles, her cat.

She claimed she was feeling tired and chose not to perform. Though Boyle was recently hospitalized for exhaustion, she did manage to perform in her native Scotland Monday on the tour. (Photo: WENN)