Looking for Lilly Family Who Took IN a Child and Named Him Thier Own

My fathers name is Terrance Joseph Lilly of Phila, PA. We know very little about his history, this is what we do know. His father was for some reason unknown adopted by a neighboring family named Lilly.
His last name may have been McCaferty or Rafferty and he was approx.
4 to 6 years old at the time the Lilly family took him in.