SALEM – A Lynn mechanic is headed to state prison for up to eight years after admitting that he terrified his elderly step-grandmother in the middle of night as he stole $16 at knifepoint from her Peabody home to support his heroin addition last January.Michael Vick, Jr., 28, of 41 Light St., Lynn, showed no emotion as he made his plea Friday morning in Salem Superior Court to charges of burglary and armed assault on an occupant, assault and battery with a dangerous weapon on a person over the age of 60 and assault with a dangerous weapon on a person over the age of 60 arising out of an incident at his step-grandmother’s home at 4 Holden St. in Peabody on Jan. 13 when he entered around 3 a.m., forced her from her bed at knifepoint and stole $16.Vick was sentenced to serve not less than five years and not more than eight years in state prison by Judge Timothy Q. Feeley.”I’ve had nightmares ever since this happened,” the now 78-year-old victim told Feeley in a quivering voice.She went on to say, “I awoke at 3 a.m. and saw a shadow standing over me. He broke into three locked doors and three o’clock in the morning grabbed my arms and threw me onto the floor.”Had Vick gone to trial, Assistant District Attorney John B. Brennan was set to introduce evidence and testimony that around 3 a.m., the then 77-year-old woman awakened with a man standing over her holding a knife, wearing a black hooded sweatshirt and a scarf that partially covered his face.”Gimme your (expletive) money,” the man demanded.The very terrified woman was forced out of bed and herded toward the kitchen where she got her handbag. The man rifled through her handbag and found $16 – three fives and a one – and fled from the premises.That particular currency was the money she had put aside for her bowling that week, Brennan emphasized.The women told authorities she thought it was Vick, because she recognized his voice. The woman sustained a minor injury to her arm, according to reports.Police said that Vick had forced open a screen door, smashed a glass window in the back door and then forced open a third door to gain entrance.Vick was arrested later outside his Light Street rooming house by police. They found three fives and a single one-dollar bill on his person as well as a screwdriver, but no knife was found.Vick told police he had no idea what they were talking about when they confronted him about the home invasion.Brennan said the woman believed the knife to be about 10 inches long, but authorities could not determine if Vick brought the knife with him or he picked it up in the house after entry.When Feeley asked Vick about the incident, Vick responded, “I don’t quite remember. It’s not clear to me what happened that night. I think I did it,” while acknowledging he agreed with the government’s case rather than go to trial and have a jury of his peers decide his fate.Had he been convicted on the burglary and armed assault on an occupant, he would have faced a minimum mandatory punishment of 10 years in state prison with a potential life sentence on that one charge.Brennan urged the judge to impose an 11-year state prison term based on the “horror” and “egregiousness” of the acts of violence, “particularly because this was her own step-grandson,” Brennan stressed.Vick’s court-appointed defense lawyer, John P. Morris, painted a picture that Vick, a lifelong resident of Lynn, always felt he was an “outcast” in the family when his mother married into the family. He did work at the family business at Bennett Street Auto Glass in Lynn where he became certified as a tire changer and light mechanic.He said Vick became addicted to marijuana at age 15 which excelled into heroin addiction a number of years ago. He tried to get off the drugs, but instead got deeper into heroin, which “led him down to this particular path.” Now his mother wants nothing to do with him and he is estranged from his family, Morris explained.Morris said that Vick’s own biological father, whom he ha