The pair, who currently live with Martin and his wife Ruby Fowler, find themselves mixed up in the drama with Isaac Baptiste as he continues to avoid taking his medication for schizophrenia.
EastEnders fans will know that Isaac has been on a downward spiral since deciding to come off his medication. As well as acting out of character, he has also become obsessed with the murder of his late half-brother, Paul, and is determined to prove that Ruby's late father, Johnny Allen is the one who killed him.
Next week will see Lola, Kim, and Patrick discuss Isaac's condition as he continues to have hallucinations. But while they might mean well, their concern is too late for Arthur and Lily, who bump into Isaac in the Square.
Later, when the kids are nowhere to be seen and Isaac is in the middle of a breakdown having barricaded himself into Ruby and Martin's house, everyone starts to fear the worst.
While Patrick tries to talk his son around, begging him to let him into the locked house, Martin and Ruby are beside themselves over missing Lily and Arthur and decide to call the police.
As they wait for the police, Martin starts to panic that he will never see the kids again... not realising that Isaac had convinced the pair to go to the park to have a picnic. Wanting the children out of the way while he confronted Ruby about Paul's death, Isaac told them that they should stay away from the Square.
But with Lily and Arthur now nowhere to be seen, will the police manage to track them down before something awful happens?
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