she realises it is much worse. Misbah rushes over to Diane's and tells them that Dee Dee may have autoimmune encephalitis. When the doctors reveal to Diane and Tony that the treatment isn't working they are forced to tell Dee Dee the truth. Diane and Tony fight when Tony suggests they tell Tegan but Diane is against it. Diane tells Tegan about Dee Dee's condition and allows her to be involved in her treatment. When Tegan suggests taking Dee Dee to Disneyland, Diane is against the idea. She is annoyed when Tegan decides to bring Disneyland to Dee Dee which causes her to fall ill. Diane cancels the party and Dee Dee tells her she wishes Tegan was her mum. Diane furiously bans Tegan from being involved with Dee Dee. Tegan responds by revealing she's going to tell Dee Dee that she is her real mum, shocking Diane. Diane and Tony try to convince Tegan to change her mind, but after seeing how much it is affecting Tegan, they decide to tell Dee Dee. However, just as they are about to tell her, Tegan arrives and tells them not to do it. Diane and Tony are devastated when doctors reveal Dee Dee will need possible fatal treatment to get better. Diane is reluctant to give her consent but Tony and Tegan persuade her to do it. Diane and Tony decide to stay strong for Ant, but after visiting Dee Dee in the hospital, Tony leaves the village, unable to deal with the heartache. Diane is worried when Tony doesn't return home and decides to report him missing. The police arrive and tell her that they found his phone discarded and all funds have been withdrawn from his account. Diane can't believe that Tony has abandoned her and tells Harry and Ste that Tony is no longer part of the family. In September 2018, Diane is told that they are running out of options for Dee Dee but they have another treatment that can seriously hurt Dee Dee. Tegan is against the idea and seeks legal advice from James. Tony returns after Ste tracks him down and Diane lashes out at him for abandoning her but forgives him as it proved to traumatic for him due to his past. After being betrayed by Harry, James tells Dee Dee and Rose that their parents are not their real parents and Diane, Tony