As reported at the weekend, Phoebe is currently sharing a squat with sixth former George Smith (Steven Roberts) as neither have anywhere else to go.
Hollyoaks introduces Phoebe in upcoming episodes as George's fellow student Callum Kane (Laurie Duncan) discovers the truth about his living arrangements.
When Callum later starts hanging around the squat, Phoebe becomes nervous - wanting him to stay away and stop interfering.
Gill told TV Times of her character: "She's streetwise. Whereas George is new to all this, she has done it for a long time. While Callum is a good friend of George's, in her eyes anyone from the 'outside' is trouble.
"She fears being grassed up. She doesn't want to go into care and she doesn't want to be separated from George. He and her dog Thunder are all she has."
When George has a falling-out with Phoebe, he ends up deciding to live on his own. However, Phoebe feels guilty as she knows that George hasn't been feeling well lately - so she has to ask Callum for help.
"By this point, George is very ill and she knows it'd be on her conscience if anything happened to him," Gill added.
Hollyoaks airs weeknights at 6.30pm on Channel 4 with a first look screening at 7pm on E4.
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