WEST BATH — A Bowdoinham teenager has been sentenced to 27 years in prison for killing his grandmother two years ago.

Dominic Sylvester, now 18, pleaded guilty Tuesday to the murder of Beulah “Marie” Sylvester. He was 16 years old when the 55-year-old woman was found unconscious in the mobile home they shared.

“Can there be anything more tragic?” Superior Court Justice William Stokes said Tuesday. “Can there be anything more heartbreaking than a young man, not even 17, who brutally murders the woman who took him in and tried to raise him?”

Sylvester bent over his knees as he listened to the emotional statements of two family members. He answered the judge’s questions throughout the hearing but did not make any statement to the court. He wore wrist and ankle restraints, and when he signed paperwork for the judge, he crouched awkwardly in his handcuffs to write his name.

Sylvester also pleaded guilty to two counts of elevated aggravated assault, stemming from two incidents when he broke his grandmother’s arm in 2016 and her wrist in 2017. The agreement included consecutive sentences of five years in prison on each count, but that time will be entirely suspended. The judge also ordered four years of probation on each, so Sylvester will have eight years of supervision upon his release.

Investigators believe Sylvester beat his grandmother to death with a stick or club.

“I’m not willing to give up on you, Dominic,” Stokes said. “I hope you don’t choose to give up on the rest of society when you get out. That will be your choice.”

Beulah Sylvester adopted her grandson when he was a baby and raised him as her own child, according to testimony. Tiffany Sylvester, who was Beulah Sylvester’s daughter and Dominic Sylvester’s birth mother, wiped tears from her face as she spoke to the judge Tuesday. She described her struggle with post-traumatic stress disorder, anger and anxiety. She said her mother was her best friend, and she put a picture of “Nana” where her other children sleep so they feel her presence.

“Nobody wanted to help her,” Tiffany Sylvester said. “Not our family, not DHHS, not the sheriff’s department, when they all knew what was going on.”

When she returned to her seat, she put her hands over her face and wept.

A central question in this case was whether Dominic Sylvester should be tried as an adult or as a juvenile.

The court held a bindover hearing to decide that issue last year. The testimony provided a glimpse of the violent and volatile life in the Sylvester home.

District Judge Beth Dobson heard four days of testimony about Sylvester’s tumultuous childhood, the assault that killed his grandmother and the boy’s life since his arrest. For years, the family had regular contact with the Maine Department of Health and Human Services and other providers. Evidence in the case included more than 4,000 pages of records from social workers, schools and police.

The state argued Sylvester was the aggressor and would be a danger to the public if released at age 21, the maximum amount of time he could remain in the juvenile system. In the adult system, Sylvester faced a sentence of 25 years to life in prison.

Defense attorneys argued Sylvester was a victim of child abuse and neglect, and he benefited from treatment and stability at Long Creek Youth Development Center in South Portland, where he was in custody at the time.

“This is a very extraordinarily difficult case on many levels: on a human level, on a legal level, emotionally,” Dobson said at the end of the bindover hearing, according to a transcript. “The state of our society, it really rings a lot of bells.”

The sentencing hearing recalled some of those same details.

Assistant Attorney General Meg Elam described a history of violence in the home, including reports of aggressive behavior when the boy was as young as 8 years old. She said case workers witnessed Sylvester kick animals and hit his grandmother as he got older, and over the years, they reported the fear that he would hurt his grandmother.

Elam also described the multiple blunt force injuries revealed in an autopsy as the cause of death for Beulah Sylvester, and she said Dominic Sylvester reported to multiple people that he hit his grandmother that day with a wooden club.

“But we do have to be mindful that he was in fact not an adult at the time of these crimes, and that during the 17 years that he lived with Beulah, he had what can only be described as a chaotic upbringing,” Elam said. “Largely because of his behavior, but also because of her well-meaning and, in hindsight, inadequate response, her fear of being separated from him so that she turned down residential placements, her covering for him when he committed crimes of violence, which perhaps if they had been disclosed might have led to interventions that would have kept us from getting here today.”

Defense attorney James Mason also asked the judge to consider the reports that Sylvester was a victim of physical abuse as well. He said he received boxes of records, including reports that the boy went to school with bruises at a young age and reported being hit at home.

“It’s not a justification, but it’s something that you should consider,” Mason said.

The judge spoke at length about the sentence, especially the need for probation upon release. He told the victim’s family that he hopes they remember Beulah Sylvester as the loving woman who agreed to take in her grandson as a baby.

“Our desire to hold him accountable conflicts with our desire to leave him with a life that is meaningful,” Stokes said. “Perhaps the biggest legacy that Dominic can lead is to honor the memory of Marie. It seems odd to say that, but he’ll have time to do it. And then the question will be, Dominic, whether you choose to do that.”

Sylvester was arrested in 2018 and held without bail at Long Creek. After he turned 18 and had been bound over to the adult system, he was transferred to Twin Bridges Regional Jail in Wiscasset. He now will be transferred to an adult prison.

The judge ordered Sylvester to have no contact with his family members after he is released.