WAKEFIELD — A soon-to-be third-grader was thrust into the middle of a grown-up situation Thursday when he claimed his stepfather, Randall Bartnick, 35, of 221 Carolina Back Road, Charlestown, grabbed him by the neck, lifted him off his feet and threw him to the ground where he hurt his hands and knees after he clogged up the toilet and refused to fix it. The child, a bright, well-spoken 8-year-old whose eyes and short-cropped hair were all that were visible above the bench where he testified in 4th Division District Court, said he told his stepfather to fix the toilet himself. He also said he loved his stepfather and was not afraid of the man seated at the table next to his lawyer Melissa Larsen.Bartnick, a pediatric paramedic at Hasbro Children’s Hospital, was found not guilty of the Charlestown police charge.Attorney Robert Craven, prosecuting for the town of Charlestown, emphasized that the young man had been consistent in his testimony. “He has told the same story over and over. His demeanor is rather extraordinary under the circumstances,” he said. He asked the boy repeatedly if he had been told what to say on the stand, to which he replied no each time. “Where do you live,” Craven asked him. The boy told Craven he didn’t know, jumping into an explanation of a split home with a visitation scenario common to many families. He said he is with his father every Wednesday and every other weekend. Although Judge Thomas T. Houlihan Jr. said he found the child’s testimony compelling, he believed information provided by others — his mom, Kelly Bartnick, a longtime nurse, a psychologist, Bennett Z. Hirsch, and Bartnick himself — proved more credible. Houlihan said he also considered information he heard regarding a bad divorce and a possibly bitter ex-husband, John Lennier, of Richmond, and his influence on his son as a contributing factor to the assault charge by the boy. The judge also considered Lennier’s owing $25,000 in back child support as contributing to some of the discord in the family dynamics.Bartnick, who has no criminal record, was charged June 26 with simple assault after the Charlestown police received a report from Rhode Island Department of Children, Youth and Families regarding an incident that allegedly occurred in April. The child reported to a social worker at school that he had been grabbed by the neck, lifted off the ground, and “thrown toward the toilet causing him to hit his head,” an assertion denied by Bartnick with a not-guilty plea in June. A social worker, according to the police report, noted the presence of a “linear petechia mark on his neck” or redness in the area.That mark, Larsen said, could have easily been caused by the child carrying his book bag on one shoulder as she demonstrated to the court during questioning of the alleged victim, who held a Batman toy in his hand during his testimony. She also pointed out it would be difficult to raise the boy by one hand because he told the court he was about 100 pounds, though his mom said he was under that, laughing a little at the child’s estimation.Kelly Bartnick, who has been with Randall Bartnick for seven years, reported there have been three other complaints to DCYF prior to the latest incident and all were unsubstantiated and believed to be because of the same influence of an ex-husband coaching his children.“They’re all my children,” Randall Bartnick said during his testimony. “He’s like my own blood.” He said he never touched the alleged victim and doesn’t believe in corporal punishment. Larsen added that Bartnick works with critically ill children everyday and has a “heightened awareness of abuse and would never abuse a child.” He responded, “No, No.” Lennier initially went to Rhode Island State Police to report the incident. Once at the Hope Valley Barracks, he said he was told to take the case to Charlestown police where the child has his primary residence and where the alleged incident occurred. Police advised Lennier to bring the child to South County Hospital for an evaluation of his injuries, which he reportedly did. In a second interview with a children’s advocacy group, the alleged victim reportedly indicated “he was grabbed by the neck and put up against the wall.” During testimony Thursday, it was revealed that the child’s older brother had made the same assertion, with nearly the same details, but DCYF did not pursue charges. Meanwhile, Hirsch, the psychologist, said he has worked with the family, which now includes three other children, in dealing with the blended family situation although he said he has only seen the 8-year-old twice in about two weeks, both after the arrest. Lennier claims the incident “is getting played down” and believes the charges should have been more significant.