Herbert and Catherine Schaible are being held on third-degree murder charges after Wednesday's preliminary hearing.
Two-year-old Kent died in 2009, followed by 8-month-old Brandon in April. Both boys died of pneumonia after a two-week illness.
The Schaibles belong to a Pentecostal church that believes in "divine healing," according to police statements read in court.
Jurors convicted the parents of involuntary manslaughter in Kent's death. That led to 10 years of probation and orders to seek medical care if another child became sick.
The couple's seven surviving children are now in foster care.
The Schaibles' lawyers say they had no intent to harm their children.
