Coronation Street spoilers follow.
Coronation Street airs a worrying new incident involving Steve McDonald and Leanne Battersby's young son Oliver next week.
The toddler has to be rushed to hospital after his seizures start to become a regular occurrence, leaving Steve and Leanne desperate for answers.
Early next week, Steve and Leanne are looking to the future as they visit a nursery they are considering for Oliver.
When they return home to the cobbles, Leanne pops into the bedroom and screams as she sees Oliver having another seizure.
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An ambulance is called, but by the time the paramedics arrive, Oliver already seems calmer. Steve and Leanne remain united in their worry over what could be happening.
Later in the week, Steve and Leanne start to relax again as Oliver seems much better. However, when Leanne's partner Nick Tilsley reads to Oliver back at home, he has his third seizure and emergency services have to be contacted again.
This time, Oliver's seizure continues even while the paramedics are treating him.
At the hospital, a doctor tells Leanne and Steve that Oliver's seizure still hasn't stopped and he'll now have to be moved to intensive care.
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Jane Danson, who plays Leanne, explained: "When he had the first seizure, obviously they were worried but they just thought he'd over-heated so they weren't massively concerned.
"It caused a bit of friction between Steve and Leanne, because he was in charge of Oliver and it happened on his watch but they get through it. However, as the weeks go on and he has these seizures more and more, the doctors start to question what is causing them.
"They run tests in hospital and they do prepare them for it being something more serious, but they don't want to speculate about what it might be.
"It's just so hard for them to get their heads round. This has come out of nowhere. A few weeks ago Oliver was fine and developing like any other three-year-old, now he seems to be regressing and no-one knows why."
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Asked whether Leanne fears the worst or thinks Oliver is going to be fine, Jane replied: "I think there's a bit of both and she goes on a real journey with it. Historically Leanne has always been a character that jumps in at the deep end then swims as fast as she can, but this is something that is totally out of her control.
"She goes on a rollercoaster ride. One minute she's worried about what's wrong with him, the next she thinks he's going to be fine because he's shown some progress. He has good days and bad days and when he has good days, she gets her hopes up again.
"It's really sad and it has a massive effect on everyone who's involved in Oliver's life. It also has a big impact on their relationships with each other and how they get through this. It's not just about this little boy, it's about everybody and how they all cope with this, and with Leanne being his mum, she's the one who seemingly doesn't cope."
Jane also spoke further about next week's episodes, which see Leanne and Steve start to realise this could be serious.
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"Leanne knows enough to be worried, but she doesn't know enough to fully understand what it means as they haven't got the clarification yet," Jane explained.
"At this point it's not concrete, so there's a little part of her that thinks he could be fine. It's partly denial, but I think that's your instinct as a human being – survival and to believe that anything might be possible. But as time goes on, I think that positivity starts to diminish.
"After the second seizure, he goes home and he's seemingly okay. He's said 'mummy' after not speaking for a while, so Leanne sees that as a positive sign. But just as things seem to be okay, he has a much worse seizure and that's when they can't stop it, so he has to go back to the hospital. That's the beginning really of this awful journey they're going to go on.
"Given what she's being told by the doctors, Leanne can't escape how serious this is now. It's just something that's incredibly sad, something that's unthinkable for most of us."
Coronation Street currently airs on Mondays, Wednesdays and Fridays at 7.30pm on ITV.
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