The pair fell out after Olly missed his wedding to compete on The X Factor in 2009.
She'd previously stated that she'd "rather not" return to the singing competition.
Not quite the news Simon Cowell was hoping for.
“My whole brain was a blur of negativity."
"It was difficult to tell him no."
She had been one of the favourites to scoop the $1m prize.
We knew that bandana looked familiar...
It's all about one 16-year-old boy this year.
There's early signs it could be its best series yet.