Declan, played by Jason Merrells, receives the bombshell news in a fortnight's time as he is told that Mia has been killed in a car accident.
The ruthless businessman is then immediately faced with a dilemma over whether to tell Jai Sharma - Mia's biological father - what has happened.
Jai (Chris Bisson) does eventually find out about his daughter's passing, but it is currently unclear whether it is Declan who breaks the news.
Emmerdale viewers saw Mia's final scenes at the end of August as Declan sent her away from the village after discovering that she was not his biological daughter.
Upcoming episodes see Declan's girlfriend Katie Sugden (Sammy Winward) left concerned by his refusal to have any contact with Mia. However, it is thought that her death comes just as Declan has finally agreed to let Mia pay a visit.
Mia was portrayed by actress Sapphire Elia, whose departure from Emmerdale was announced in May.
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