The model was one of the former contestants who re-entered the famous house on Tuesday (3 January), as the ‘All Stars And New Stars’ series kicked off on Channel 5.
During her entrance chat, Nicola branded Brian “crap”, having hosted the show when she was first a contestant in 2012.
Her comments came after current presenter Emma Willis questioned why she’d decided to return, given she’d previously branded her last stint as “the worst decison of [my] entire life”.
“I’m here because you’re here,” she told Emma.
“Brian Dowling was so crap and horrible to me during my exit interview but I know you’ll be amazing.”
The jibe left Emma open-mouthed in shock, before she said: “Nicola! She’s not even in there and she’s already started, the little minx.”
Brain was axed as host and replaced by Emma in 2013, having taken the presenting baton from Davina McCall when the show moved to Channel 5 in 2011.
He previously won ‘Big Brother 2’ in 2001, before being crowned the Ultimate housemate in a special series that concluded its run on Channel 4 in 2010.
“It was horrible in there. Everything was horrible,” she said at the time. “Honestly, it was probably the worst decision of my life to go in there.
“Please take my advice. Not a lot of people take my advice, but go and eat bugs in the jungle - do not go into the ‘Big Brother’ house.”
‘Celebrity Big Brother’ continues on Wednesday at 9pm on Channel 5.