Tracy (Kate Ford) has falsely accused Becky of causing her recent miscarriage, but the truth is finally exposed at the schemer's wedding next week.
Once Becky has obtained her enemy's medical records to clear her name, she wrecks Tracy and Steve's (Simon Gregson) big day - getting the last laugh.
After watching the dramatic episodes at a preview screening, Kelly told The Sun: "I hope people will be cheering for Becky when they watch the episode. Tracy has been so mean - she set out to destroy Becky and that's what she did.
"It's great that Becky gets to go out with a bang - she drops the bomb then leaves the carnage behind."
Becky leaves the cobbles shortly after her revelation as Kelly decided to bow out from Coronation Street last year.
"I'm so glad they didn't kill her off - that would have been too easy," Kelly continued. "This way, she's always going to be a cloud hanging over Steve because she could come back at any moment."
Coronation Street airs Tracy and Steve's dramatic wedding on Monday at 7.30pm and 8.30pm on ITV1.
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Watch a preview of Friday night's Coronation Street double bill in the video below: