Police said 31-year-old Renae Bellis from Boscobel, a small town in southwestern Wisconsin, is charged with first-degree reckless homicide and obstructing an officer.
"We all have worked many years in law enforcement, but any time there's the death of a child, and even more so an infant, it affects us and it makes it very challenging," Boscobel Police Chief Todd Stenner told reporters at a news conference Tuesday, according to SWNews4U.com.
Bellis is scheduled to appear this week in court.
Police in Boscobel responded to a call early Saturday morning about a dead baby found in a family home, Stenner said during the news conference.
Authorities said Bellis told them that late the night before, she heard her baby "wailing" after the girl's father returned home from work and that she found him holding the child "with both hands at arm's length and shaking her," according to a criminal complaint.
Bellis told investigators that after the father fell asleep, she went to check on the child - and realized the infant was dead.
She said she went back to bed, according to the complaint, then called her mother the following morning.
The coroner ruled the death a homicide by blunt force, and police arrested the baby's father, 39-year-old Mark T. Rand.
During the investigation, authorities said, Bellis displayed little emotion - returning to the residence and showing investigators a blood-stained onesie decorated with a ladybug pattern, according to the criminal complaint.
On Sunday, when Bellis showed up at the Grant County Jail to bring Rand some personal items, investigators used the opportunity to question her again.
"At that time, the detectives received a confession from Renae, and she was responsible for the injuries to the child, and had lied the previous day to law enforcement," Stenner, the police chief, told reporters.
Bellis began to "break down" while talking to investigators and suggested that she was "kind of depressed" and that she took it out on her baby, police said.
Police said Bellis told them that she was trying to feed the baby a bottle, but that the three-month-old was fussy and would not take it.
The infant, she told police, "kept screaming and screaming and screaming," according to the criminal complaint. The mother said "that she snapped and slapped her on the face," the document states.
Bellis, police said, explained that her baby would not stop crying; so she "hit her again" and then slapped her on the buttocks.
Police said Bellis told them she used the ladybug onesie to wipe the blood from her daughter's body.
Bellis said she then shook the child and put the child, who was still crying, in her swing; later, when she stopped crying, Bellis said, she thought she was sleeping, according to the complaint.
She said she did not tell the baby's father what had happened.
Authorities announced Sunday that Rand, the father, had been released - and that Bellis had been taken into custody and charged in the child's death.
The autopsy revealed numerous bruises on the infant's face, head, neck and buttocks, and "pools of blood" in the brain, according to the complaint.
Police said Bellis claimed she was depressed when she killed her daughter.
The Centers for Disease Control and Prevention reports that 1 in 10 women experience frequent symptoms of postpartum depression, which can include feelings of indifference toward the baby, doubt about being able to care for the baby or concern about hurting the baby.
Kimberly Pearson, a psychiatrist and assistant professor of psychiatry at Harvard Medical School, told ABC News that about 50 percent of women who have had postpartum depression will likely have it again.
"If they've had true postpartum psychosis, than the risk is 75 to 80 percent that they'll have a recurrence," she said. "Certainly, if somebody is experiencing psychotic symptoms, it can lead them to psychotic behavior."
Police, however, have not said whether Bellis was suffering from postpartum depression.
Bellis is being held at the Grant County Jail. It's unclear whether she has an attorney.
© 2016 The Washington Post
(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)
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