CHICAGO (CBS) — A teenager is behind bars, accused of having sexual conduct with young children cared for by his mother in far north suburban Winthrop Harbor.

WBBM Newsradio’s Julie Mann reports the arrest stems from an investigation of a licensed residential daycare facility operated by Cheryl Degler in Winthrop Harbor.

Degler’s son, Brett A. Degler, 17, has been arrested and charged with three counts of predatory criminal sexual assault of a child and four counts of aggravated criminal sexual abuse. Police began the investigation after strange marks were found on a child, by concerned parents who called local police.

“They had some concerns that their child, they thought, had some kind of unusual marks on, you know, their body, and we started at that point,” Winthrop Harbor Police Chief Joel Brumlik said.

LISTEN: WBBM Newsradio’s Julie Mann reports

According to Brumlik, detectives looked into the complaint and officers determined there were three victims between the ages of 4 and 11 years old. The abuse allegedly happened during a five month period starting in November 2011.

The teenager lives in the home where his mother ran the daycare, but Brumlik said the mother didn’t know about the abuse.

“There’s nothing, from a criminal point of view that we can determine, that she had any complicity with what was going on; or she had any knowledge of what was going on,” Brumlik said.

However, the woman has surrendered her daycare license.

“It’s very disturbing … especially to have it here in the community, and have parents that entrusted their children to this care facility to have to now go through this,” Brumlik said.

Police have not had contact with Brett Degler in the past. Parents who use the daycare have been contacted and police believe they have identified all the victims.

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