Katie Sullivan

Katie has been tormented for her father, Frank, her whole life, made to feel like an outsider and isolated from her sister and mother. To deal with this isolation Katie turned to alcohol and drugs, which led her down a dark path and resulted in her tragic disappearance from her home in San Myshuno. Katie's upbringing has caused her to always feel like an outsider, and she often feels no one can relate to the isolation she feels.

Season 1
Katie returns to her mother, Claire and sister, Stacey, on Christmas night in their new Newcrest home, one year after mysteriously disappearing in the midst of an alcohol addiction.

Season 2
Claire tries to go back to the way things were and strengthens her bond with Katie, but Stacey is angry due to Katie's secrecy on her disappearance. Katie wants to throw a welcome-home party to naturalise her return, so Claire organises one at the Verdant. Stacey blames Katie for being distant and secretive and Katie ignores her. Mary Munroe tries to obtain gossip from Katie and Stacey steps in, blaming her sister for placing so much emotional strain on her family. In the heat of the argument, Katie's father Frank returns. Frank tries to make amends, but Claire is livid as he was a bad father in San Myshuno and Katie remains distant. Later, Frank and Katie argue about Frank emotionally abusing Katie and telling her to leave San Myshuno. Katie threatens to tell Claire and Stacey about Frank's depravity but Frank violently threatens her. Claire and Frank reconcile and rekindle their romance, much to Katie's dismay. Katie meets Deano Malloy, a new arrogant boy in town who takes a liking to her. Claire announces her and Frank plan to remarry, leaving Katie devastated. Katie and Frank have a heated conversation in which Katie secretly records Frank's depravity with a video camera. She warns Claire to refrain from marrying Frank and Stacey accuses Katie of trying to ruin things for the family. Katie's grandmother Jeanie Harris arrives for the wedding and jokes at Katie's addiction problems. At the wedding, Katie struggles to keep her silence as Frank and Claire marry. At the Wedding reception, Stacey blames Katie for trying to ruin things and a fight breaks out; Stacey slaps Katie in front of everyone. When Frank makes a speech, Katie plays the recording from earlier to everyone and exposes Frank's depravity to all. She reveals Frank made her leave San Myshuno and storms out of the wedding. She struggles to refrain from drinking alcohol when Deano stops her and invites her to his house, where the two sleep together. Katie dismisses Deano the morning after and expresses her feelings of neglect to a guilt-ridden Claire. She is later shocked to learn she is pregnant. She tells Claire and Stacey, before scarily breaking the news to Deano, who surprisingly responds with excitement. Katie feels hopeful about the future and views a baby as her way to have control over her life, something she has never had due to Frank's abuse. Katie is later pushed down the stairs by Frank, waking up in hospital to learn she has miscarried. She is unsurprised to learn Deano has relapsed and confesses Frank pushed her, something which she has been keeping quiet. Katie later discharges herself and visits him in the Red Rosa Bar, telling him she will kiss his gravestone when he is dead. Frank then throws her out into the storm and disowns her in a fit of rage.

Season 3
Some time after Frank is mysteriously murdered, Katie has begun work at Cava Coffeeshop as a barista. She is approached by Deano and tries to reach out to him, but he refuses to open up and continues on his path of alcoholism. Katie is visited by an old friend from the streets, Louise Smith, who she catches up to speed about her dad and the list of unanswered questions he left behind. Louise urges Katie to find the answers from Claire, so Katie storms into Claire's school office and demands the truth. Claire's boyfriend Milton Stubbs tries to stop Katie, but she yells at her mother and is slapped as a result. After having countless flashbacks of her father's abuse, Katie pours herself a glass of wine and comes extremely close to relapsing, before overhearing a devastating truth told by Claire to Milton: Frank was not Katie's dad - in truth, Claire was raped and Frank was forced to pretend Katie was his, hence the extreme hatred Frank directed at Katie throughout her upbringing.