Nicholas Dominici’s dad said he had hoped to have a photo of his son’s kindergarten graduation four years from now.

“But sadly what I have is a reminder of his death,” Otoniel Feliz said, weeping as he held up a photo of his son. The toddler died last month after he and three other young children were sickened by what officials said was exposure to fentanyl at their Bronx day care center.

Feliz joined Bronx District Attorney Darcel Clark and other officials as they announced the indictments on charges including murder and manslaughter of the center's operator, her husband and the husband's cousin in Dominici's death. He was 22 months old and had spent only a few days at the Divino Niño day care center when he died on Sept. 15.

Clark said day care operator Grei Mendez, 36, her husband, Felix Herrera Garcia, 34, and Carlisto Brito, 41, were arraigned Thursday and ordered held without bail.

Mendez and Brito were arrested after Dominici and three other children under Mendez's care showed signs of opioid exposure. Herrera Garcia, who authorities say fled to Mexico, was arrested there and then extradited to New York.

Dominici was pronounced dead at a hospital. The other three children, ranging in age from 8 months to 2 years old, were treated for what authorities said was fentanyl exposure.

Investigators said a kilogram (2.2 pounds) of fentanyl was found in a closet in the day care center and 6 kilograms (13.23 pounds) of fentanyl, heroin and other controlled substances were found under a trap door in the floor beneath a padded mat where children napped.

“This is a catastrophe,” Clark said. “Our sorrow is matched only by the outrage because these babies were used as shields to protect a narcotics operation.”

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Clark said the children “are my children, they’re our children and it’s our responsibility to make sure we do all that we can to keep them safe and to protect them.”

Andres Aranda, an attorney for Mendez, said his client knew nothing of any fentanyl operation. “She is not guilty,” he said.

Messages seeking comment were left with attorneys for Brito and Herrera Garcia.

The defendants and a fourth person also face federal narcotics charges.

Feliz, Dominici's father, spoke alternately in Spanish and English as he described how Mendez had earned his trust over the little boy's brief time at the day care center.

“We feel betrayed by that day care,” he said, "because they would send us photos, would send us text messages with everything that happened throughout the day. We trusted them because we saw it was a place that would keep us informed.”

Feliz thanked those working on the case, but said, “Everything that is done will not bring my son back.”