A Hibbs woman and another man had forcible sex with her son when he was 7 years old and again when he was 13, Pennsylvania State Police said.
While at Highlands Hospital in early January, the boy, now 15, told investigators his 35-year-old mother and a 70-year-old man named Elmer Plum sexually abused him, state police said.
He told state police his mother inappropriately touched him and later had sex with him, state police Trooper Heather Clem wrote in a criminal complaint.
Most of the abuse happened in a home on Hatfield Road in Menallen, Fayette County, state police said.
The Pittsburgh Post-Gazette has chosen not to identify the boy's mother by name as it could identify her son.
State police said the boy's mother at first denied the sexual contact when interviewed by investigators, but then later said, "If I did, I don't remember doing it."
Mr. Plum is accused of inappropriately touching, then later raping, the same boy when the child was 7 years old, Trooper Clem wrote in the complaint.
The boy also told investigators Mr. Plum had inappropriate contact with a girl. The boy police Mr. Plum would lock the bedroom door with just him and the girl inside, according to the complaint. The girl would be catatonic after the encounter, according to the complaint.
When interviewed by investigators, Mr. Plum denied all allegations and stated, "I'm over the stage of messing with kids," Trooper Clem wrote in the complaint.
The girl locked in the room with the boy, now 10 years old, was also molested by another man, 29-year-old Joshua Wolfe, of New Salem, state police said.
Police said the girl told her therapist that Mr. Wolfe "hurt her" by touching her inappropriately, according to the complaint.
State police said the girl was anxious and could not be interviewed.
When interviewed by police, Mr. Wolfe admitted he touched her genitals, but that the two didn't have sex, Trooper Clem wrote in the complaint.
The boy's mother is charged with statutory sexual assault, incest of a minor and indecent assault.
Mr. Plum is charged with rape, involuntary deviate sexual intercourse, sexual assault, aggravated indecent assault, two counts of indecent assault and two counts of corruption of minors.
Mr. Wolfe is charged with aggravated indecent assault, indecent assault and corruption of minors.
The three are in the Fayette County Jail on $250,000 cash bond each.
Molly Born: firstname.lastname@example.org, 412-263-1944 and on Twitter: @borntolede.