Bennett Pladl, a 7-month-old baby, was found dead at a home on Earlston Court after a welfare check Thursday morning.
Later in the morning, police in Connecticut found two people fatally shot inside a pickup truck in New Milford.
Police identified the deceased as Katie Pladl and her adoptive father, 56-year-old, Anthony Fusco. Steven -- her biological father and the father of her child -- was found dead of a self-inflicted gunshot across the state line in New York.
"It is Steven's mother who called us this morning to make the request to make the welfare check at that location," Knightdale Police Chief Lawrence Capps said. "As our officers arrived on scene we found the infant inside. There was no one else inside the residence. There is a connection between the events in Knightdale today and the crimes that are being investigated by the New Milford, Connecticut, police department and the New York state police department.
"Obviously we're very saddened by today's events," Capps added. "Events like this are not common in our community. Unfortunately, they're not uncommon in society. Like you, we're trying to make sense of all the factors that led up to this senseless taking of life."
Katie was legally adopted out of state when she was born. When she turned 18, Katie reached out to Steven and her mother through social media. In August 2016, she moved in with her biological parents and their two other children.
Steven and his wife legally separated three months later, in November 2016. The wife told authorities that the month she moved out of the home Steven had been sleeping on the floor of Katie's bedroom.
The wife also said that she learned her daughter was pregnant and that Steven was the father in May 2017 after reading one of her other children's journal. She said that she contacted Steven and he admitted that Katie was pregnant with his child and that the two had plans to get married.
Warrants said the two young children were told by Steven to refer to Katie as step-mom, even though she's actually their sister.
The baby was born in September 2017.
"This is a quiet community. A bunch of average people. Middle-class people," said Ronnie Hogg, a Knightdale resident who lives nearby. "I knew who they were only because of the news for what they did. They'd only been here since January."
Hogg said the complicated couple kept to themselves.
"They never bothered anyone. They were nice people. I saw the baby - I saw the girl taking the infant in and out of the house but that's about it," Hogg said. "It's upsetting that the baby is dead but how long had the baby been there, so yeah, it's pretty bad."