The Courier-Post reports a judge granted Anita Saunders request this week.
Justin Robinson pleaded guilty last August in adult court to aggravated manslaughter in the October 2012 slaying of 12-year-old Autumn Pasquale in Clayton, the Philadelphia-area town where both lived. Robinson is now 17.
Anthony Pasquale claims Robinson's parents, who are no longer married, should have known he "posed a risk to third parties."
His suit seeks damages for pain and suffering, along with funeral expenses. It also includes a wrongful death claim against Robinson and several claims of negligence against his parents.
Autumn Pasquale was killed after she went to Robinson's house, which was several blocks from hers, after receiving a Facebook offer to trade bike parts. When she didn't return home that night, her family, then the entire community, set off in a frantic search.
Two days later, her body was found in a recycling bin behind the home next to Robinson's.
The break in the case came after Saunders contacted authorities because she saw something that bothered her on one of her sons' social media accounts as the community searched for Autumn. Her older son also initially was charged with murder in the case, but the charge eventually was dropped after Robinson said he acted alone.
The older boy's case was handled in juvenile court, and he was released from custody last September.
Information from: Courier-Post (Cherry Hill, N.J.)