Prosecutors say a 41-year-old Nebraska woman had sex nightly with her teenage son when he was in seventh and eighth grade.

The Fort Calhoun woman has been charged with first-degree sexual assault and made an initial court appearance Wednesday. Her bond has been set at $30,000.

County attorney Don Kleine says the boy, now 15, reported the alleged abuse to a counselor, who notified police.

Investigators say the boy told them his mother was addicted to prescription painkillers when the alleged abuse took place.

The Associated Press is not identifying the woman to protect her son's identity because he is the alleged victim of sexual assault.

Fort Calhoun is 13 miles north of Omaha.