The first to go was daughter Jennifer, a mere eight days old when she died on January 3, 1972. An autopsy listed the cause of death as acute meningitis, and since the baby never left St. Clare's Hospital after her birth, authorities consider her death the only case above suspicion. We may never know what psychic shock waves were triggered in Marybeth Tinning's mind by the death of her new-born daughter, but more of her children soon joined the casualty list.

Less than three weeks later, on January 20, two-year-old Joseph Tinning, Jr., was pronounced dead on arrival at Ellis Hospital, in Schenectady. Doctors blamed his death on a viral infection and "seizure disorder," but no autopsy was performed to verify those findings. Four-year-old Barbara Tinning died six weeks later, on March 20, and autopsy surgeons, lacking an obvious cause of death, attributed her passing to "cardiac arrest." Barbara's death was the first reported to police, but officers closed their file on the case after a brief consultation with hospital physicians.

And the deaths continued. When two-week-old Timothy died at Ellis hospital, doctors were once more unable to determine a cause, tossing his case into the grab-bag of Sudden Infant Death Syndrome (SIDS). On September 2, 1975, Nathan Tinning died at the age of five months, an autopsy blaming his case on "pulmonary edema." SIDS was the culprit again on February 2, 1979, when Mary Tinning died six months short of her third birthday, while no cause was ever determined in the death of three-month-old Jonathan, on March 24, 1980. Three-year-old Michael Tinning was still in the process of being adopted when he was rushed into St. Clare's Hospital on August 2, 1981. Physicians could not save his life, and while they viewed his passing with a "high level of suspicion," the cause of death was still listed as bronchial pneumonia.

The real questions began on December 20, 1985, when three-month-old Tami Lynne Tinning was found unconscious in bed, blood staining her pillow. Rushed to St. Clare's Hospital, she was beyond help, and while doctors ascribed her death to SIDS, they also telephoned the state police. An investigation led to Marybeth Tinning's arrest on February 4, 1986, after she confessed to pressing a pillow over Tami Lynne's face when the child "fussed and cried." In custody, she also confessed to murdering Timothy and Nathan, but staunchly denied harming any of the others. "I smothered them with a pillow," she told detectives, "because I'm not a good mother."

On July 17, 1987, Tinning was convicted of second-degree murder in Tami Lynne's death, jurors acquitting her of "deliberately" killing the child, blaming her for a lesser degree of homicide through her "depraved indifference to human life." With trials pending in two other confessed slayings, husband Joseph Tinning seemed bewildered by the whole affair. In newspaper interviews, he admitted occasional suspicion of his wife, but had managed to push it aside. "You have to trust your wife," he said. "She has her things to do, and as long as she gets them done, you don't ask questions."