Benidorm actress Sheila Reid was also among the guests for A Christmas Corrie, based on Charles Dickens's classic tale A Christmas Carol.
Reid and Daybreak host Kelly play police officers who are seen arresting show regular Tina McIntyre (Michelle Keegan) in the mini-episode.
Kelly commented: "I am absolutely beside myself. I am a massive fan of Corrie and have been since I was a little girl.
"It's always been an ambition of mine to appear, even if it's just in the background of the Rovers having a hot pot or a pint of stout, but this is even better as I get to play a character."
Meanwhile, Little Mix perform in the Rovers, and Dawn's popular character Vera Duckworth returns as a ghost.
Little Mix star Jade Thirlwall said: "We've watched [Coronation Street] for years and years. Since we were little, and to be here is surreal but it's amazing, isn't it?
"It's really nice being a part of Text Santa, but at the same time doing something we've always wanted to do."
Text Santa airs on Friday, December 21 from 8pm on ITV1.
Watch a preview of this year's Text Santa in the video below:
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