Kate Connor was shocked to find heartbreaking messages revealing the extent of Carla's mental health deterioration on Coronation Street.
Grieving Kate was given her late wife Rana Habeeb's mobile phone, which was recovered from the factory collapse - and the phone contained 57 missed calls from Kate's half-sister Carla.
In her paranoid state Carla, who has gone missing, believes Rana is still alive and has been leaving messages for her.
Kate, who has been blaming Underworld boss Carla for the collapse of the factory that killed her wife, listened back to one of the messages.
And she was stunned to hear a broken Carla pleading to Rana: "I'm so sorry. Please just talk to me."
The messages proved to Kate how deeply Carla has been affected by the roof of the factory caving in.
One fan said: "Heartbreaking."
Another said: "Omg those voicemails from carla."
Kate took the phone to Rana's brother Imran in the hope that he would also forgive.
"It's Carla leaving a message for Rana last week. And there's loads like this, asking her to come back, telling her that she's got lots of people after her, real paranoid stuff," she explained.
"It seems like she needs help pretty quickly."
But Imran was left unmoved.
Carla's partner Peter Barlow and his father and Ken have been worried for Carla after she scribbled the words “watching” and “murder” on a crossword and threw her tea down the sink convinced she’s being poisoned after being blamed for the tragedy.
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As her paranoia swirled out of control she fled the street barefoot, escaping via the medical centre window.
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