Investigators found the bones after searching a fire pit at the home in Wheatfield last month.
New details have been released on what led to the arrest of Samantha Jo Sebella and Steven Valle as documents released in court Friday outline an alleged confession.
In a probable cause affidavit, investigators said Valle told someone he knew last month, "I killed two of my kids." He allegedly told that acquaintance, who later went to police, that he smothered the couple's first-born child and drowned their second before burning both their bodies in their home's fire pit.
The Jasper County Sheriff's Office said the couple, who have a four-year-old son who was born at home and whose birth was never registered, initially told investigators they had no other children or ever experienced a miscarriage or still born birth. But on their phones, authorities said they found messages indicating Sebella could have been pregnant "on three separate occasions," as well as several messages from her to Valle, calling him "Baby Killer."
During a search of the home on Monday of last week, two K-9 units alerted to the burn pit and to a pile of ashes near the garage. Investigators said they dug up bone fragments that are still being tested to confirm they're human.
Two days later, Valle allegedly told investigators that twice in recent years Sebella gave birth alone at home, and that he found both babies dead shortly after they were born.
He told authorities he buried them in the backyard, only to dig them up years later to burn them in the fire pit.
In a statement, his attorney Mark Van Der Molen said, "Mr. Valle is presumed innocent. I intend to fully examine the State's case as it unfolds."
Sebella and Valle are due back in court in December.