Roy Eller, of Oxford, was convicted on charges of sexual assault, unlawful contact with a minor, and related offenses, the Chester County District Attorney's Office said in a Friday release.
Last month, the victim's mother pleaded guilty to endangering the welfare of a child after the girl told investigators that her mother was aware of the abuse and wanted her to have a child with Eller, authorities said.
An investigation was launched in April 2019 when county detectives learned that a teen girl was being sexually abused by her mother's boyfriend, the DA's office said.
Eller, according to the victim, forced her to engage in oral sex and sexual intercourse with him, authorities said.
During the trial, the victim's mother admitted that she had witnessed Eller sexually assaulting her daughter but blamed her for it, according to the DA's office.
“The horror of what this child endured while her mother’s boyfriend sexually abused her is inconceivable," District Attorney Deb Ryan said.
"It’s all the more tragic because there was no responsible adult in that house to whom she could turn for help. I hope this guilty verdict will allow the victim to begin moving forward with her life.”
Eller will be sentenced at a later date.
Call Childline at 1-800-932-0313 if you suspect a child is being abused.
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