An Ohio day care worker recently pleaded guilty to raping and photographing children in her care.

Heather Koon, 27, pleaded guilty last week in Lorain County Court to four counts of rape for sexually abusing infants and toddlers and three counts of illegally using a minor in nudity-oriented material, the Chronicle-Telegram reported.

Koon abused the children, ages 1 to 3,  in March and April of 2013 while she worked at ABC Kidz Child Care in Elyria, Ohio, reportedly on the orders of her fiance James Osborne, and also photographed children while later working at ABC Kidz and Country Day School in Amherst.

Osborne, 37, also pleaded guilty last Thursday to four counts of complicity to rape and related charges.

Koon had passed state and federal background checks before being hired, according to Fox 8 Cleveland.

The couple were arrested after Osborne, already a registered sex offender on probation, was arrested at Koon's Elyria home, where he was illegally living instead of an address he gave in nearby Oberlin, Ohio. Osborne previously pleaded guilty in 2010 to charges related to child pornography found on a computer he brought in for repairs in 2007.

At the time of the arrest, Osborne had a laptop and an iPhone with a sexual picture of a teenage girl, the Chronicle-Telegram reported, despite his probation barring him from using the internet. 

"Deputies seized the iPhone and laptop and found videos and images of Koon sexually abusing the children on the phone," the Chronicle-Telegram reported. "Prosecutors have said previously that Osborne would use his phone to tell Koon what he wanted her to do to the children at the day care centers where she worked."

The couple face 15 years to life in prison, and could face life without parole if they are deemed persistently dangerous sexual offenders.

Parents of victims said their children, some of whom did not remember the abuse, had gone through therapy but were struggling with trusting adults, as were the parents, according to the Chronicle-Telegram. Several parents involved have also filed lawsuits.

Osborne is already serving another eight-year sentence for violating his previous probation.