Two Massachusetts parents accused of feeding their baby a bottle of formula with heroin in it were charged with manslaughter on Friday.

"Thirty-year-old Ryan Barry and 26-year-old Ashley Cyr are accused of killing their 5-month-old baby girl after she ingested formula laced with heroin." (Via WHDH)

"The couple was indicted by a grand jury this week on manslaughter charges nearly two years after the youngster died." (Via NECN)

WFXT reports investigators found evidence in the parent's apartment shortly after the baby's death. including three grams of heroin and hypodermic needles. Investigators also found traces of heroin in the baby's bottle.

It took the prosecution two years to build its case. As for what may have happened that day, Plymouth First Assistant District Attorney Frank Middleton said,

"Barry told cops after the baby's death that he used bottled water to prepare her formula and that someone may have used that bottle to clean a syringe. … Barry also told police that Cyr 'even once went as far as snorting heroin on an open Dr. Seuss book, then leaving it open on the floor for kids to get at it.'" (Via Boston Herald)

Middleton said the baby's mother, Cyr, is also facing charges because she allegedly "allowed heroin into the bedroom, where the victim and her two small sisters, 3 and 4 years old, lived, along with a number of adult drug users." (Via Boston.com)

As for the defense attorney and the baby's grandmother, they maintain the parents are innocent.

Defense: "I certainly didn't hear any evidence that my client was knowingly involved in this tragedy."

Barry's Mother: "They didn't do anything, I don't know how they came to this conclusion." (Via WCVB)

Boston.com reports the baby's father has a criminal history and that he pleaded guilty to raping a minor in 2006. Both parents pled not guilty and are on $200,000 cash bail.

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