Katy goes into labour at the Weatherfield community centre in a week's time, just as she is busy acting out the role of Mary in the local nativity play.
As the production reaches the birth scene, the audience are impressed by Katy's realistic portrayal of labour - unaware that it's not a performance at all! When a frantic Katy asks for an ambulance to be called and chaotic scenes follow, will dad-to-be Chesney (Sam Aston) turn up on time for the birth?
Here, Georgia May Foote - who plays Katy - chats to Digital Spy about the storyline.
How do you feel about getting a big Corrie Christmas storyline?
"I was quite shocked when I heard that Katy would be giving birth around Christmas time! I remember when I was reading the scripts and realised that it was going to be one of the main storylines for Christmas. I was excited and just wanted to make sure I did it justice, really."
What can you tell us about the episodes which see Katy give birth?
"It all happens at a Christmas play that Faye is supposed to be taking part in, but in the end, she bottles it - she says that she doesn't know her lines and she doesn't want to do it. The only other person who knows Faye's lines is Katy, as she'd been helping her to prepare, so Sunita and Leanne ask Katy to step in.
"Katy is playing Mary, and just as they're doing the scene where Mary and Joseph are asking if there's any room at the inn, Katy begins to feel a bit hot and she starts getting pains. Soon after that, she realises that she's in labour and it all goes from there!"
Is Katy scared during the labour or has she prepared herself for it?
"Well, she's definitely quite shocked and the fact that there's so many people there makes her nervous at first, but she always knew the baby was due around this time. She's a little bit scared that she's not giving birth at a hospital, which is where she'd feel most comfortable. Obviously you don't expect to be giving birth in the middle of a play!"
"Yeah, there definitely is. When I was reading the scripts, I was thinking, 'Giving birth as Mary in a stable - you can't get any more cheesy!' But it's been done in a really nice way. It's a bit tongue in cheek and a bit of a joke, but at the same time it's going to be really nice to watch. There's some really nice scenes."
Chesney also faces a bit of a race against time in the episodes…
"Yeah, you see how Chesney is trying to get to the community centre in time for the birth, which is going to be really funny. At the same time as Katy is in labour, Chesney is riding a bicycle trying to get there in time. He's in an elf costume after spending a day working at the garden centre!"
With Chesney absent, does Katy get much support from anyone else?
"Anna is there to support her - she's had a kid herself, so she knows what to expect. And then you'll have to watch and see whether Chesney makes it back in time for the birth!"
"I was really nervous leading up to doing the scenes, and there was quite a long wait to do them. We filmed the storyline out of sequence, so I filmed quite a lot of scenes which take place after the baby arrives before I'd actually filmed the birth. But then the shoot for these scenes finally came up.
"It was a bit strange, but I had Debbie Rush who plays Anna there with me along with a midwife, and they were both really good and gave me loads of advice. In the end, I was actually quite pleased with how the scenes went - I think they went really well. It definitely wasn't as bad as I thought it would be."
Are you pleased with the choice of baby name - Joseph Peter?
"I'm surprised it's not Jesus! (laughs) They've obviously gone for the next best thing instead by choosing Joseph. It's a nice name, and then they've chosen Peter as a way of remembering Schmeichel the dog, so that's really nice too."
In real life, there's been some babies arriving in your family in the past year, so did that help you with the storyline?
"Yeah, definitely. I was there when my sister went into labour so I got an idea about the contractions and things like that. Also, one of my aunties has just had twins, and then another of my aunties has just had a baby too, and my cousin has as well - so babies just seem to be everywhere at the moment! I'm used to being around newborns, which is quite nice."
How have you found working with the baby?
"It's been really good. I've had a year of looking after baby Hope when she was quite small, so I had a year's worth of practice before this actually happened. I was quite lucky in that respect."
We often expect doom and gloom from the soaps at Christmas, so are you glad to be getting a festive storyline which should have us all smiling?
"Definitely - I think it's going to be really nice. I remember when I was reading the scripts, I was thinking, 'Hang on a minute, this is all a bit too nice - what's going to go wrong?!' But I think that's what they're aiming for - I think it's going to be quite a nice Christmas. Most people are happy and there are some really nice scenes coming up after the birth, where Joseph has been brought home and brings everyone together. The extended family all comes together, so it should be great to watch."
> Read more from Coronation Street's Georgia May Foote in Soap Scoop