The Benidorm actress, 53, took offence to Sharp, 50, who in a rallying cry called on younger contestants to partake in bushtucker trials.
"So Crissy and the young girls. So what about the young girls, Crissy? Shall we let them have a go?" Rock responded: "Yes, let them have a go."
However, Rock complained privately: "I feel like a t*t because that's the first time I ever heard anybody in this camp go, 'You'd better come back with stars'. That's why I said, 'We don't need that crap'. That is unfair that he made it about our ages that we were incapable of doing it."
Campmates eventually agreed that Emily Scott would do the trial. She returned with a maximum number of stars, earning 11 meals for the celebrities.
Fun House star Sharp later took a swipe at ITV1's Benidorm, in which Rock starred as Janey York from 2007 until this year.
"What do you think about Benidorm? Was it the funniest TV show you'd seen? Because I didn't get it. I found myself watching it but didn't find it funny," Sharp told her. "It was really clichéd and I found myself detached from the people in it like Johnny Vegas and his mum."
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