Their son, Wyatt, died Aug. 28, about two hours after he shot himself in the head with his father's .40-caliber handgun, state police said. The Matteaus were at their apartment with their son and infant daughter at the time, but Wyatt was alone in a room when the gun fired, troopers said.
His mother had told him to stay away from the gun moments before the accident, warning him that it was "Bad boo boo's," according to a police report.
Connecticut law makes it a crime to store loaded firearms in an area where the owner reasonably should know that someone under 16 could find them.
After the accident, officials removed the couple's daughter from their custody and placed her with a relative.
The parents declined comment as they left the courthouse. Their lawyers, William H. Paetzold and Christopher McCarthy, said they were preparing for the case and declined further comment.
The couple posted bail and were scheduled to return to court Nov. 19.
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