It wasn’t until several weeks later, after the mother had been admitted to the hospital, that police discovered the child’s body.
How the alleged relationship started
According to court documents reviewed by WPXI, Kennedy had lived near the girl's family and even worked with her father for several years.
In November 2017, while the young mother remained in the hospital, police interviewed her parents about the relationship she had with Kennedy.
The girl's father said that in October 2016, Kennedy and his girlfriend broke up. For several months, he did not have a place to live until he moved in with them in January 2017.
Police said the girl admitted that their sexual relationship began about three years prior to her giving birth, while Kennedy was still living with his girlfriend near her family's home.
Once Kennedy moved in, the girl's father told police the two became inseparable. In some cases, they would stay home together during family outings, and in other cases, they would go out together while the family stayed home.
The girl's father said she grew standoffish toward her 22-year-old stepsister after the older girl gave birth in early 2017. This was set off when the older girl made a comment about the younger girl's relationship with Kennedy, according to the criminal complaint.
Pregnancy and abortion attempts
While it's unclear when the 15-year-old got pregnant, police said she had several conversations with Kennedy about terminating the pregnancy and made several attempts.
During an interview with police, the girl admitted she tried to end the pregnancy by taking vitamins and herbal supplements that were known to cause pregnancy complications and premature labor.
The girl said that in August, she and Kennedy began devising ways to end the pregnancy and agreed that if she miscarried, she would say that the baby was not his.
Several conversations between Kennedy and the girl also included descriptions of physical violence that could be used to end the pregnancy, according to the criminal complaint.
According to police, the girl gave birth in a bathroom at her home on Oct. 9, 2017, which was Columbus Day.
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Alleged cover-up and the teen's hospitalization
When first interviewed by police, the girl said she had been home alone when she gave birth and that she strangled the baby and hid the body. During a follow-up interview, she admitted that she had been lying to protect Kennedy.
The teenager told police Kennedy was downstairs in the home when she gave birth. According to the criminal complaint, he then went into the bathroom with her and strangled the baby before hiding the body inside a bag.
On Oct. 20, 2017, the girl told her parents that she had fallen down the stairs, and she was eventually taken to the hospital.
About two weeks after being admitted to the hospital, the girl was placed on a ventilator. According to police, the girl has since spent eight months in the hospital, undergone 35 surgeries and continues to receive medical treatment because of the supplements Kennedy convinced her to take.
Investigation and arrest
Shortly after she began receiving medical treatment, the girl admitted that she had been sexually assaulted and given birth.
Police became involved on Nov. 13, 2017. That same day, they discovered the safe containing the child's body inside the teenager's bedroom closet. The baby's body had been covered in cement.
On Nov. 15, 2017, police interviewed the young mother, and during this interview, she said that she had killed the baby after giving birth.
In the following few days, police searched the home a second time, and during an interview on Nov. 20, 2017, the girl said Kennedy had actually killed the infant and she had been lying to protect him.
The young mother took a polygraph test in April 2018 about the child's death, and, according to police, she passed.
Kennedy was arrested on Nov. 21, 2018.