State police unearthed the remains in the dead of night at a tidy house in Farmingdale after being told by the boy's mother that he died two years ago. The circumstances of his death remained unclear Saturday.
The boy, Justin Kowalczik, was about 17-months-old when he died in the summer of 2010, police said. Authorities said the family never reported the child's death.
"It is absolutely a suspicious death and it is being investigated as such," said State Police Major Patrick Regan. "We don't have a cause of death, and to our knowledge, there was never a report made of the child being missing."
Investigators were trying to determine how the child died and why the family kept it a secret.
Officials with Suffolk County's Child Protective Services agency initially went to the home Wednesday to check on the health of one of the woman's three children. They grew concerned when the family couldn't account for the whereabouts of a child born in 2009.
That led to a police interview of the mother, Heather Kowalczik, who told them the child had died shortly after the family moved to Farmingdale from Orange County two years ago, Regan said.
On Friday, police sought Kowalczik's boyfriend, Robert Rodriguez, who is the father of her two older children, ages 6 and 9, but not
of Justin. As of Saturday afternoon, he had refused to answer questions, Regan said. "He did not come in willingly. He is not cooperating," Regan said.
Neither Rodriguez nor Kowalczik had been charged with any crimes.
Kowalczik's two surviving children were in the custody of county child welfare agents, police said.
When neighborhood resident Meade Jackson was asked how she would describe the Rodriguez', she said that they were a nice family.
Investigators tell Eyewitness News that the investigation began after a tip from state police in Middletown, New York.
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