Hysterical, the mother brought her 4-year-old, severely beaten autistic son to the police station and handed over a bag with three of his bloodied teeth, she told investigators.

The night before, she had entrusted her boy to the care of her then-boyfriend, Nicholas Kernechel, 28, of East Greenville, Montgomery County, before going out with friends.

In Montgomery County Court on Monday, the mother watched, surrounded by family members passing tissues to each other, as Kernechel was sentenced to two to 10 years in state prison, with time served, on charges of simple assault, endangering the welfare of a child, recklessly endangering another person, and false reporting. A felony charge was dropped as a part of a plea deal that the prosecution said was aimed at keeping the victim from testifying.

"You are, and always will be, a monster who abused a child with special needs," said the mother in a statement read aloud by Deputy District Attorney Samantha Cauffman.

The incident occurred the night of July 18, 2015, according to prosecutors, when the 4-year-old was in the sole care of Kernechel. After returning the next morning, the woman said, she found her son around 9 a.m. asleep on the floor of his bedroom, his face beaten, his lips swollen, and three teeth missing from his mouth.

Hospital reports said the boy's teeth and other injuries were consistent with their having been extracted. Kernechel claimed that he dropped the boy and that his face had hit his nightstand. However, prior signs of abuse, including bruises, were found as far back as April 2015.

"I was a mother who trusted you with my son," the woman wrote. "I completely failed him as a mother."

Addressing the judge, Kernechel expressed remorse and detailed how his heroin addiction had wreaked havoc on others. He also mentioned a past offense for DUI, marijuana possession, and theft to support his drug habit. He said he was high the night of the assault.

In response, Montgomery County Judge Steven T. O'Neill said that he had handled cases involving addicts before but that given the heinous nature of the injuries, Kernechel's message was lost on him.

"Those were not the actions of a heroin addict on the nod," O'Neill said. "They were not the actions of someone who smoked pot chilling out."

Along with his prison sentence, O'Neill ordered the defendant to take part in a drug-and-alcohol program.

Although the dropping of the felony count against Kernechel significantly reduced his sentencing, Cauffman said she was satisfied with the outcome.

"Since the defendant's arrest, that child is on the path to getting better and being in a better place," Cauffman said. "Making him go through the rigors of a trial would have set him back so much."

610-313-8119 @coltshaw_