Contestant Mitchell Callaway, who was publicly slammed for his "rude" attitude by judge Guy Sebastian on Monday night's episode, has been accused of taunting teenage rival Declan Sykes, who has Asperger's syndrome.
A show insider told the Herald Sun that Callaway has been "stirring up" some of the contestants by pricking them with a pin backstage, which caused Sebastian to humiliate him on live TV.
Sykes's mother Katherine, however, denied that there is a problem between her son and Callaway, saying: "Declan and Mitchell's relationship is absolutely fine. They are together all the time. In the one instance their mucking around turned boisterous. I'm also with Declan every day. And as every parent knows, boys will be boys."
A Channel Seven spokesperson added: "Declan's mother Katherine is completely right. Furthermore, the culture inside the X Factor production would not allow bullying to survive."
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Callaway's mentor Natalie Bassingthwaighte revealed earlier this week that the wannabe singer considered quitting the show after Sebastian's comments but he revealed yesterday that he wants to stay because quitting is "not the Aussie way".
Sebastian also apologised to Callaway, saying: "You always have to have a great attitude. You always have to show love and respect to everybody that you come across [but] I'm truly sorry for upsetting Mitchell and for choosing the wrong time to say that."
Watch Mitchell Callaway perform in Monday night's episode of The X Factor below: