NORTHAMPTON, MASS. (WHDH) - Following a lengthy investigation and indictment, a judge on Wednesday accepted a guilty plea from a father charged in the 2019 death of his four-month-old son in western Massachusetts.

According to the Northwestern District Attorney’s Office, Isaac Villalobos, also known as Angel M. Carattini-Rivera, pleaded guilty in connection with the death of his child, who authorities say died after being given adult sleep medication via an infant syringe.

During a change of plea hearing on Wednesday, Villalobos, a former resident of Amherst, Mass., was sentenced to serve five to seven years in state prison.

In a press release, the DA’s office said that in exchange for pleading guilty to a charge of Assault and Battery on a Child Causing Substantial Injury, the Commonwealth dropped charges related to manslaughter and reckless child endangerment, as well as a charge of Assault and Battery with a Dangerous Weapon on a Child Under 14.

Villalobos was first arraigned in July 2022, following a three-year investigation into the circumstances behind his four-month-old son’s death and an indictment by a grand jury.

The infant reportedly died on Sept. 15, 2019, “as a result of receiving adult sleep medicine,” according to the DA’s office. The Office of the Chief Medical Examiner later determined the cause to be acute doxylamine intoxication.

“This was a horrific tragedy,” said Assistant District Attorney Andrew Covington in a statement. “In this case, the Commonwealth wanted to provide a measure of closure for the victim’s family while also holding the defendant accountable for his actions. We feel the best interests of justice were served with this plea and sentencing today.”

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