SALEM – A Salem Superior Court jury began hearing testimony Tuesday in the trial of a Marblehead school janitor charged with raping his 7-year-old half-brother at North Central Street home in Peabody some 25 years ago.Richard Jones Jr., 42, of 29 Auburndale Road, Marblehead went on trial this week on one count of rape of a child with force stemming from incidents occurring between November 1982 and May 17, 1986 in which he allegedly forced his step-brother to engage in manual genital stimulation and oral sex while the family was living at an apartment located at 11 North Central St., in Peabody.The jury comprised of seven women and seven men, including two alternates, heard opening statements and some testimony Tuesday.Assistant District Attorney Kim Faitella told the jury “you will hear about the house of horrors” that Jones created and how his 7-year-old half-brother laid on a bed “terrified as his assailant was over him.”After describing the alleged forced sex acts, Faitella emphasized to the jury the half-brothers? gap in age, saying, “This was a 17-year-old adult and he was 7 years old.”Faitella told jurors that they will hear from the mother of the victim entered their home early one afternoon and found both boys naked in bed, with Jones leaning over her son, and how she was “distraught and nervous.The mother then called her husband at work but thought this was the first time this type of conduct occurred, Faitella added, and the mother never thought to ask a question after that. She never reported it to the police.Defense lawyer Jessica Thrall painted a different picture, saying, “It was no secret the family was not a happy home.”According to Thrall, two separate families were living in the Curwin Circle projects in Lynn and fell apart. The defendant?s father, David Jones Sr. then married the victim?s mother and the couple had one son together – the victim in the case.Thrall admitted that David Jones Jr. was not the “model older brother.”The family, she maintained, had financial problems and she emphatically pointed out to jurors that if the mother had walked in on them, “Would she really do nothing?”Thrall insisted there is “reasonable doubt,” and that the charges do not make sense.The mother of the victim testified that, in 1982, the family, with her daughter and their son, moved to the Peabody apartment. Richard followed shortly afterward.The family stayed in Peabody until the victim was age 8 and then moved to Manchester, N.H.She described how she came home from work early one day and saw Richard and her son in a bed, both naked, and Richard kneeling over her son. “I didn?t want to believe what I saw. I was in denial.”She described how she called her husband but hung up because she was afraid what he might do to Richard.The victim, now age 33, is expected to take the stand today and describe his version of events and tell jurors why he waited so long to report it to authorities.At the time of his arrest, Jones was a Marblehead elementary school janitor at the Coffin School. He has since been placed on administrative leave, pending the outcome of his case.A conviction on the charge carries a life sentence in state prison.Jones remains free on bail but has other pending rape and assault charges involving alleged sexual misconduct with his teenage step-sisters, which he denies.