Magazine reports have revealed that Mandy (Nicola Stapleton) discovers her mother Lorraine has died later this month, leaving plans for the ceremony in doubt.
The drama plays out as Mandy remains hesitant about marrying Ian (Adam Woodyatt). She eventually has a heart-to-heart with Tanya Jessop (Jo Joyner), confessing that her troubled relationship with Lorraine is the main reason for her trust issues.
Tanya suggests that Mandy should try to resolve things with Lorraine, but when the mischievous blonde heads to the hospital to do so, she hears that her mother has passed away.
Ian, whose behaviour becomes increasingly erratic after hearing Ben's guilty secret, later shocks everyone by insisting that the wedding should go ahead regardless of Lorraine's passing.
The businessman's persistence particularly annoys Lucy, who has been frantically trying to cancel the wedding arrangements to sabotage the ceremony.
EastEnders fans already know that Mandy will soon be leaving Walford, but with Ian insisting that the wedding should take place, what will happen on the big day?
The wedding week begins on Monday, May 21 at 8pm on BBC One.