Luka begins to develop a relationship with Serena Bishop. Svetlanka tells Luka that she spoke to a nurse from the hospital where he was born, and she confirms that he is not adopted. Luka does not believe her and he hides in an old storage shed, with Serena being the only person who knows he is there. Luka and Serena grow closer and he tells her about the fire he started. Serena later decides that she wants to lose her virginity to Luka, but before she does, she receives a call telling her that her mother, Liljana, was in hospital. Liljana requires a liver transplant and Svetlanka tells Karl Kennedy (Alan Fletcher) that Luka could save Liljana. Svetlanka tells the rest of the family that Luka may have the same blood. Sky Mangel (Stephanie McIntosh) uses a radio to put out a call for Luka and he hears the message and goes to the hospital. Luka is a match and he is taken into surgery. Svetlanka sees Serena and Luka together and tells Serena the truth about her half-brother. Just as Luka goes to leave town, Serena blurts out that Liljana is his mother in front of her family. Luka is happy that he has found his mother, but Liljana struggles to find any feelings for him. Luka and Serena become friends and Liljana and Luka get to know each other. Liljana's husband, David (Kevin Harrington), finds the situation difficult and Serena finds it hard to share her mother with Luka. Liljana invites Luka to move in with them, but David tells Liljana that Luka cannot be trusted. Luka wants to find his real father, but he discovers that Ivan had died. When he hears Liljana tell David that she did not love Ivan, Luka takes David's suitcase and burns it. Serena confronts Luka when the suitcase is returned and eventually persuades Luka to return to Perth and get some help. Liljana tells him that she loves him and he leaves. Jeremy Levi, played by Roger Neave, made his first screen appearance on 21 September 2004. Jeremy was a Psychiatrist at Erinsborough Hospital. After Izzy Hoyland (Natalie Bassingthwaighte) begins suffering from nightmares, her partner, Karl Kennedy (Alan Fletcher), decides to send her to a psychiatrist.