A trial is under way for a Pennsylvania couple that allegedly began grooming their son for sexual activity when he was 8 years old, forcing him to have sex with his mother and exposing him to pornography.



In court on Thursday, the boy, now 14 years old, told jurors that he had frequent sexual encounters with his mother while his father give him instructions and tips on what to do.



A day earlier, prosecutors described how the boy was living in deplorable conditions and unable to use utensils to eat or tie his shoes when removed from the home in August 2010.



The Plymouth, Luzerne County couple faces charges of endangerment and corruption of minors. The father is charged with conspiracy to commit rape and distributing sexual material to minors while his mother is charged with rape of a child and incest.



During their testimony, the boy's parent deny the allegations. His mother said that her weight and a car accident left her unable to have sex.



Closing arguments are expected Friday.



