A 17-year-old boy was charged Friday with raping a 9-year-old girl inside a “swine barn” at the Maryland State Fair. The boy and the girl’s families were friends, according to Baltimore police, and often traveled to fairs together. The Baltimore County Crimes Against Children Unit found that the boy may have been sexually abusing the girl since she was 3 years old. The girl told police that he had “forced her several times a year to engage in sex acts at different fairs in Maryland and elsewhere.” The boy has been charged as an adult with second-degree rape, second-degree sexual offense, perverted practice, fourth-degree sexual assault and second-degree assault. He is being held at the Baltimore County Detention Center on $500,000 bond.