Donna Windsor in Emmerdale is terminally ill.
Viewers discovered in last night's episode that the returning character, played by Verity Rushworth, is suffering from a rare form of cancer which can't be treated.
Donna was rushed to hospital by her stepfather Bob Hope (Tony Audenshaw) after hitting her head and feeling woozy, but once alone with the doctor, Donna revealed the extent of her medical issues.
She said: "I know what's wrong with me and you're not going to be able to sort it. I did bang my head, but that's not why I went dizzy. I've got Mesothelioma.
"I have regular check-ups back home. They monitor me - there's nothing they can do, really. It's terminal."
Donna recently returned to the Dales and sprung a major surprise on ex-husband Marlon Dingle (Mark Charnock) by revealing they have a daughter, April.
The terminally ill returnee has been eager for Marlon to get to know their child, and it seems this is due to her cancer diagnosis.
Verity, 28, has returned to 'Emmerdale' for a five-month stint after initially playing Donna for 11 years between 1998 and 2009.
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