LAKE GEORGE — Hours before her son, Gary Carpenter III, died Friday, Jennifer Mattison wrote to the man accused of killing the child and told what it was like to see and touch the 5-year-old's nearly lifeless body just before the boy was flown to Albany Medical Center Hospital.

"(T)hey had a breathing tube in his throat," Mattison told Brandon Warrington, her live-in boyfriend, "and he was ice cold."

As Warrington awaited arraignment on a second-degree murder charge Tuesday, the Warren County District Attorney's Office filed in court reams of evidence used to charge the 24-year-old Glens Falls man and Mattison with multiple felonies related to the boy's death. Correspondence between the couple, a lengthy statement to police and more than six hours of videotaped interviews with investigators failed to shed light on precisely how Gary died, but illustrate in cold detail the suffering the child endured and what prosecutors say are the calculated lengths the couple took to avoid blame.

Gary died Friday night at Albany Med from a blow to his head. Mattison called police Thursday morning and said her son had fallen off his bed in the Mission Street home she shared with Warrington, struck his head and wasn't responsive. Prosecutors believe Warrington slammed the boy's head into a wall or floor. While interviewing Mattison, investigators told her that a medical exam showed that Gary was also sexually abused the morning he was assaulted.

"I love you. I can't believe this happened," Mattison wrote to Warrington. "I really wish you would have let me deal with Gary then this wouldn't have happened ... This is why I told you that you can not (sic) correct him like a teenager."

When he arrived at Albany Med, prosecutors say Gary had a fractured skull, injuries to his rectum and genitals and bruises to his arms and neck. The child's body temperature was more than 10 degrees below normal and his lips were blue.

"I never meant for any of this to happen ... Please stay by my side," Warrington wrote to Mattison. " ... I wish I could just fix it all ... I (heart) you baby forever and ever! Please forgive me."

Mattison and Warrington were arraigned within an hour of each other on Tuesday in Warren County Court. Mattison has been charged with felony reckless endangerment, hindering prosecution and misdemeanor endangering the welfare of a child for allegedly waiting more than an hour to call 911 after finding Gary injured, and then lying to police. In addition to murder, Warrington was charged with manslaughter and endangering the welfare of a child. Both entered pleas of not guilty and were sent to Warren County jail.

Mattison sobbed during her arraignment as Assistant District Attorney Kevin Donlon repeated the grisly results of her son's medical exam. As Warrington was led out of court, a woman who identified herself as one of Gary's aunts screamed, "I hope you rot in hell!"

Mattison and Warrington have a 3-week-old son named Braxton. During her five-hour interview with investigators in Glens Falls on Thursday, Mattison is shown on tape cradling Braxton in her arms, rocking the child back and forth in a swivel chair and, at one point, changing his diaper on the police station floor. The boy is now being cared for by Child Protective Services.

"Tell Braxton I love him," Warrington wrote to Mattison, saying later that, "If you still love me after all this we should get married."

In their interviews with investigators, both Mattison and Warrington constantly altered the timelines and events of Thursday morning and the days before.

Mattison initially told detectives that Gary fell earlier in the week and that she found him on his bed Thursday morning unresponsive and with his toes and hands twitching. At first adamant that Gary was never alone with her boyfriend, she speculated that Gary could have jumped onto his bed, fallen off and hit his head on a wall, where both she and investigators say there is a large dent.

"That's impossible," one investigator said. "The bed would have to be several stories tall."

After Mattison told police she never saw Warrington strike Gary, investigators continued to press, telling her they believed she was trying to protect her boyfriend.

"Do you understand that by not telling us the truth (doctors) may not be able to treat him?" an investigator says. "And the more time that you don't tell us the truth, the more of Gary's life is taken away."

Mattison then told police she had seen Warrington slap Gary before and eventually said she saw him push Gary to the ground the morning the child was found unconscious and that she heard a thud from another room a little while later.

In his interview with detectives, Warrington quickly told them that "(Gary) is a klutz" and that he tripped and fell on his own that morning.

"I don't believe that for a (expletive) minute," one investigator replied harshly.

Warrington at first told police repeatedly that he had not pushed Gary, but later said Gary "pissed him off" and that he shoved the boy toward his room at 8 or 8:30 a.m. on Thursday.

"It wasn't intentional, it was accidental," Warrington said, adding later, "I want to see him. I feel so bad."

Neither Warrington nor Mattison could explain how Gary could have been sexually assaulted. Mattison also said it took nearly an hour to call police because she couldn't get good reception on her cellphone.

Both Mattison and Warrington became emotional during their interviews with police, crying, stuttering and struggling to come up with answers for investigators' questions.

After police ended their interview with Mattison, a Child Protective Services worker spoke with her.

"How are you doing?" the woman asked. Mattison hung her head and replied, "I'd be better if I was with (Gary)."

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