The Utah Court of Appeals has refused to dismiss charges against a couple accused of killing their baby in 2006 by sleeping with him — their second child to die in bed with them.

The appeals judges sided with a lower court in a pair of opinions released Friday concerning the death of 3-month-old Kayson Merrill. The infant died while in bed between his father, Trevor Merrill, and mother, Echo Nielsen, both 28, of South Jordan.

The judges said that while a state medical examiner listed the official cause of death as "undetermined," there was enough evidence that "co-sleeping" caused the baby to suffocate to put the parents on trial.

The parents, whose first child also died while sleeping with them in 2003, have been charged with child-abuse homicide and reckless endangerment. They have pleaded not guilty.

Defense attorneys argued there wasn't enough certainty to go to trial after the medical examiner also cited illness and low birth weight in his report.