The family of a Bronx 2-year-old left in critical condition after allegedly being exposed to fentanyl at his day care –– where another toddler died and two others were left seriously ill — was reeling Saturday.

“It’s all just too much right now,” said the boy’s devastated mother, whose 8-month-old daughter was also hospitalized after authorities said she was exposed to the deadly drug at the day care.

When the distraught Mom Sought Answers from Divino Nino Day Care owner, Grei Mendez de Ventura, the woman said only, “I don’t know what happened,” the child’s grandmother told The Post.

“So much irresponsibility. They are babies,” the woman, who did not want to give her name, fumed. “It’s her job to care for them, protect them. She needs consequences.”

Nearly a kilo of fentanyl, and multiple kilo presses, were found inside the day care, sources said.

The drugs were found in the rear of the tiny apartment.

The children are believed to have inhaled the deadly substance.

Mendez de Ventura and a man she sublet a room to at the day care, Carlisto Acevedo Brito, have been taken into police custody in the case.

Drug charges are pending and a third suspect is being sought, sources said.

The grandma showed The Post a disturbing photo of her 2-year-old grandson passed out, face up, laying on a playmat on the floor, with his 8-month-old sister passed out in a crib next to him.

The family initially thought the boy had died, she said.

“What? How? Where?” she cried out, after the child’s parents called her.

“The daycare,” the kids’ father answered, after seeing his son unconscious and that his daughter “couldn’t breathe,” the grandmother said.

Both were rushed to Montefiore Hospital and administered multiple doses of Narcan.

The boy remains in critical condition and the girl was in stable condition late Saturday afternoon, police said.

Four children were at the day care Friday, she said.

The baby girl is “doing better today, but she’s on a lot of drugs,” the grandmother said, but her brother “is not doing well.”

Lamented the grandmom of her devastated daughter and her husband: “She’s a good mom. She takes good care of her kids. They have all the love for them,” she said of the couple.

“I can’t believe this happened. I really can’t,” she said, tearing up.