Louis Walsh's real name was apparently revealed to the X Factor studio audience on Saturday.
The judge's mother Maureen, who was in the audience, explained that Walsh's real name is Michael Vincent.
His mum made the revelation in an interview with the show's warm-up man during an advert break.
A show insider told The Sun: "The warm-up guy was speaking to guests to keep the audience on a high. At one point he had a chat with Maureen.
"I don’t know if he’d been tipped off but he decided to ask Maureen if Louis was his real name and she said it wasn’t. It was hilarious; nobody could believe his real name was so ordinary.
"When Simon Cowell came back into the studio he admitted he had no idea of Louis’s secret and thought it was brilliant.
"Poor Louis was a bit red-faced. He got well and truly set up by his old ma, intentionally or otherwise."