An Upper Darby couple with a history of drug use have been charged in the death of their 10-month-old daughter, who authorities said died after ingesting a derivative of fentanyl.

Joseph B. Milano, 31, and Lauren Semanyk, 34, face charges of third-degree murder, involuntary manslaughter, conspiracy, and other crimes in the months-old death of Angelina Milano, authorities said at a news conference Thursday at Upper Darby police headquarters.

Police responding to a 911 call found the infant dead when they arrived at the couple’s home on the 5000 block of Westley Drive in the township’s Clifton Heights section about 1:20 a.m. on April 16. Milano ran outside to greet them with the baby in his arms, screaming that she was not breathing, according to an affidavit of probable cause.

Milano initially told the officers that Angelina had drowned in the bathtub, but an autopsy showed that she had no water in her lungs, said Michael Chitwood, Upper Darby police superintendent. A toxicology report indicated the child had ingested 3-Methylfentanyl, a chemical analog of the synthetic opioid fentanyl.

"It’s sad,” Chitwood said Thursday as he announced the results of a seven-month criminal investigation. “I’ve got a great-grandchild that old who happens to be a little girl. It hits home. ... It didn’t have to happen.”

The couple gave conflicting and evolving accounts of the events leading up to Angelina’s death, before Semanyk eventually admitted “it was possible” that the infant had ingested heroin, according to the affidavit of probable cause.

The affidavit said events unfolded in this way:

In the early evening on April 15, Milano was home with the baby and her 8-year-old sister while Semanyk, a licensed practical nurse, worked the night shift at ManorCare Health Services in Yeadon. Milano told police he had been watching television in his bedroom when he went to check on the baby. He said he found her on the bathroom floor “looking out of it and groggy” with a piece of blue wax paper in her mouth.

In an attempt to revive the infant, he told police, he held a wet towel to her forehead and ran her head under cold water from the tub’s faucet. He called Semanyk at work several times and asked her to come home immediately. Semanyk told investigators she came home within five minutes, listened to the baby’s chest with her stethoscope, rubbed her sternum, performed CPR, and rubbed her back for several minutes before the child spit up water.

The couple spent several hours deliberating what to do about the ailing child. About 10:45 p.m., Milano called 911, but promptly hung up. When the dispatcher called back, Milano said the call had been “a mistake and everything was OK.”

Angelina’s condition, however, worsened and at 1:17 a.m., Milano again called 911 and asked for an ambulance. By the time help arrived, the baby’s skin had turned gray and she had no pulse.

She was taken to Delaware County Memorial Hospital, where she was pronounced dead at 2:02 a.m.

Milano was in jail on a driving-while-intoxicated count when authorities charged him with the death of his daughter. Semanyk turned herself into police around 5 p.m. Wednesday. Both were being held without bail.

The couple’s other daughter was sent to live with relatives, said Chitwood, who was joined at the news conference by Delaware County District Attorney Katayoun M. Copeland, Upper Darby Mayor Thomas Micozzie, and Police Detectives William Sminkey and Thomas Thompson.

“A family has been destroyed,” Copeland said.