After only learning a matter of weeks ago Emma (played by Alexandra Mardell) was his daughter, he’s now in for some more shocking news as it is revealed she may have inherited his dad Jim’s illness.
It’s been a dramatic few weeks for the McDonald family, as Steve (Simon Gregson) recently made the discovery Emma was his long lost daughter.
And he is set to be left terrified as she collapses for unknown reasons later this autumn.
In upcoming scenes, Emma will start to feel unwell, and leaves the salon to head to the doctors.
However, before she can make it there, she falls to the floor and is discovered by Gary Windass (Mikey North) who calls for help.
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As Emma remains unsure what her mysterious symptoms could mean, Steve is concerned she may have inherited Jim’s (Charles Lawson) myotonic dystrophy.
Speaking to The Sun, an unnamed Coronation Street source said: ”Emma’s not going to understand what’s wrong with her but her dad Steve knows only too well what it could be.
“Jim’s illness skipped a generation with Steve but the possibility of it affecting Emma is almost too much to contemplate.
“It’s going to be a really harrowing time for the McDonalds if it’s what caused Emma’s collapse.”
Recent weeks have seen the Emma struggle to cope with the revelation, however the two finally seem to have bonded.
If Emma does indeed have myotonic dystrophy, it could bring further heartbreak, and is sure to pave the way for a difficult time for the McDonalds.
Actress Alexandra, who plays Emma, is planning on sticking around, telling the Daily Star: ”I’ve just signed a new contract and I’m more than happy to stay for as long as they’ll have me.”
“You’ve got people that have been in the show for decades, and I think you need to clock up at least five years before you feel any different,” she added.
Therefore, is a return for Jim on the cards this year?
If she has inherited the disease, he might well need to be on hand to guide her through the illness.
However, Jim did not leave himself a lot of friends in the cobbles, so if he does indeed return, it’s sure to be dramatic.
Coronation Street continues tonight at 7:30pm on ITV