FAIRFIELD — The owner of a now-shuttered, illegal home day care has been charged with manslaughter in connection with the death of a 4-month-old at the home in March.

Carol Cardillo, of Edgewood Road, was arrested Thursday and charged with second-degree manslaughter, second-degree reckless endangerment and risk of injury to a minor in the death of Adam V. Seagull. Originally thought to be a result of Sudden Infant Death Syndrome, an autopsy and toxicological tests showed the infant, who lived in Shelton, had high levels of Benadryl in his system.

Cardillo called 911 on March 22 around 3 p.m. to report that the infant was unresponsive. She told police Seagull had been given a bottle around noon and then put down for a nap. When she went to check on him, according to police, she could not wake him up.

There were seven other children at the day care center in Cardillo’s Edgewood Road home, which she ran — without a license — for 11 years. The center was shut down that day, police said.

Police said Seagull showed no signs of trauma and the child had not been sick.

While praising his detectives’ work in getting to the bottom of why the infant died, Police Chief Gary MacNamara said they did a fantastic job, adding, “not forgotten in all of this is, there is a family that lost a child.”

Seagull was called “little prince,” “tootie muffin” and “little man” by his family.

On June 4, the Office of the Chief Medical Examiner reported the autopsy to detectives, which listed the cause of death as acute diphenhydramine intoxication and the manner of death as homicide.

Diphenhydramine, commonly known as Benadryl, is an antihistamine drug that should not be administered to children under the age of two and should only be administered to children between the age of two and four years old after consultation with a doctor.

After receiving the autopsy, detectives worked in conjunction with the State’s Attorney’s Office, the Office of the Chief Medical Examiner and several medical professionals and determined that probable cause existed for the arrest.

Cardillo was released after posting a $250,000 bond and is scheduled to appear in state Superior Court in Bridgeport on Sept. 15.

GReilly@ctpost.com