The babysitter didn’t speak at first when the firefighters pushed through her doorway on Feb. 15, 1985. Nancy Moronez simply stepped into her three-bedroom home in a neighborhood on the north side of Milwaukee and pointed.

“There it is,” she said, according to recently filed court documents.

An 11-week-old baby girl was slumped in a plastic chair. The newborn’s skin was tinted blue and icy. No breaths stirred in her chest. She was dead. As Moronez would later tell authorities, she had been babysitting the child for one of her husband’s co-workers. She fed the baby, then left her in her chair while she washed out the bottle. When Moronez returned, she found the baby lifeless. The Milwaukee County Medical Examiner’s Office later determined the baby girl had died of Sudden Infant Death Syndrome (SIDS).

But for one of the firefighters on the scene that day — Lt. John Kuster — the grim scene inside the house was eerily familiar. Almost a year earlier, Kuster had been on a call to the same address. Again, the emergency was a lifeless child, a 6-month-old boy. Again, Moronez was babysitting at the time. Again, the medical examiner later ruled that the cause of the baby’s death was SIDS.

Moronez herself recognized Kuster from the earlier call. “Do you remember me?” she asked the firefighter.

“Yeah, I remember,” he answered.

“I told my husband I didn’t want to babysit anymore,” Moronez replied.

Today law enforcement says the original 1980s SIDS diagnosis masked murder.

On Friday, Moronez was charged with three counts of second-degree murder in Milwaukee County Circuit Court. Police allege the defendant killed the 11-week-old baby in 1985 and the 6-month-old boy in 1984 as well as her own 2-week-old son in March 1980. The belated discovery came after Moronez’s own daughter came to police with suspicions about her mother in 2015, jump-starting an investigation that eventually led to a confession, according to a criminal complaint filed Milwaukee County Circuit Court.

“I can’t take kids that constantly cry,” Moronez allegedly told police in a recent interview cited in the complaint.

Moronez, now 60, made her first appearance in court last Friday. Court records indicate she has yet to enter a plea.

“Interestingly, it doesn’t seem like there was any kind of criminal investigation involving Mrs. Moronez until very recently,” her attorney, Matthew Meyer, told The Washington Post on Sunday evening. “I’m looking forward to investigating the matter further, and checking into numerous issues, including why it took law enforcement 38 years to point a finger at my client. It shouldn’t take 38 years for the cops to solve three alleged homicides.”

Distinguishing between SIDS and foul play is a growing concern in the medical community.

The condition — defined as the “unexplained death, usually during sleep, of a seemingly healthy baby less than a year old” according to the Mayo Clinic — was first officially identified in 1969. Five years later the Sudden Infant Death Syndrome Act of 1974 devoted federal funding and U.S. Public Health Service resources to the problem while raising awareness in the mainstream.

A massive public campaign helped cut down the death rate since the 1990s. But today, the Centers for Disease Control and Prevention still estimates that around 2,000 infants deaths each year are attributed to SIDS.

But a SIDS diagnosis can also create a blind spot. As Kent Hymel, a member of the American Academy of Pediatrics’s child-abuse committee told ABC News earlier this month, it is difficult “to distinguish at autopsy between SIDS and accidental or deliberate asphyxiation with a soft object.” This has prompted the academy to issue a recommendation this year that all suspected SIDS cases be investigated by a child abuse expert.

In 2015 Moronez’s daughter told police her mother had admitted to killing her own baby in March 1980 when Moronez was living in the Milwaukee suburb of Franklin, Wis. According to the criminal complaint, Moronez told investigators that on the morning of her baby’s death, he had begun crying for no reason. She phoned her doctor’s office. The nurse told her the baby was just having a bad day. “[Moronez] stated that this was bad advice and that she felt helpless,” the criminal complaint states.

Moronez gave the baby a bath to calm him down. While he was in the water, Moronez allegedly admitted to holding “him down and felt him wriggle a little under the water.” After the child stopped breathing, she “took him out of the tub, dried him off, diapered him, and dressed him before calling rescue personnel.”

An autopsy was performed on the baby, resulting in a cause of death of SIDS. Moronez’s son was just 18 days old when he died.

In her interview with investigators, Moronez also allegedly admitted to killing the two children she was babysitting in 1984 and 1985, respectively. According to the criminal complaint, she said that the 6-month-old boy had been crying, she was “frustrated” and “didn’t know where to go.” She smothered the boy with his blanket, holding the fabric “real tight against the face.”

A year later, she also suffocated the 11-week-old baby girl with a blanket, pinching the infant’s mouth and nose before the baby “turned kind of bluish.”

Moronez told investigators that after she killed her son, she gave birth to a daughter. She made a promise to God, according to the complaint, that she would not do anything to hurt the child if she was crying.

“I made a promise,” Moronez allegedly told investigators. “But I broke it.”

The meaning of that comment is unclear — not only is Moronez’s daughter very much alive but she is the reason police took a fresh look at the decades-old deaths.

Court records indicate Moronez will appear again in court on Thursday for a preliminary hearing.

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