Phoebe opens up over her turbulent background in upcoming episodes, telling Rhys Ashworth (Andrew Moss) that her wayward mother Mel is a prostitute.
The revelation helps to explain why Phoebe was living on the streets with George Smith (Steven Roberts) when she was first introduced to viewers at the beginning of the year.
Gill told Inside Soap: "The reaction from viewers [to Phoebe] is a bit hit and miss. Steven has such a big following, and fans are very loyal to George.
"So when Phoebe's nasty to him, they tell me to stop being a bully! I hope that when they find out about Phoebe's past, they'll change their minds about her."
Rhys and his wife Jacqui (Claire Cooper) eventually agree to let Phoebe stay with them for the foreseeable future. However, Gill added that it will be interesting to see whether the teenager is free of Mel for good.
"Jacqui and Rhys convince Mel that her daughter should stay with them in Hollyoaks," the actress said. "While this could be the last we see of Mel, I don't think she'll give up easily. She doesn't want her kid, but she doesn't want to get any hassle from the authorities either."
Hollyoaks airs weeknights at 6.30pm on Channel 4 with a first look screening at 7pm on E4.
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