EDITOR’S NOTE: This story contains the discussion of sexual violence; it also contains references to suicide. Help is available if you or someone you know is struggling with suicidal thoughts or mental health matters. In the US, call or text 988, the Suicide & Crisis Lifeline.

“Mom, I’ve got to tell you something.”

It was an evening in late October 2012, the leaves turning orange in Mindy Sigg’s Denver suburb, when her life turned upside down.

The single mother of two had come home from work and taken a shower when she found her 17-year-old sitting in her bed.

“Is this,” she asked, “about Jessica?”

“Yeah,” he said. “I’m a monster.”

For weeks, the community of Westminster, Colorado, had been consumed by the disappearance of 10-year-old Jessica Ridgeway, who had vanished earlier that month while walking to school. Days earlier, police had announced Jessica was dead, part of her body having been found and later identified as the missing girl.

Soon, Sigg was on the phone with Westminster Police, sharing with them the news that would upend her life –– and send her firstborn son to prison for the rest of his.

“Hi, I need you to come to my house,” she said, according to a recording of the call. “My son wants to turn himself in for the Jessica Ridgeway murder.”

‘I brought this child into the world’

Faced with an unthinkable dilemma for a parent, Sigg called police to help turn in her son, Austin Reed Sigg, for a violent and heinous crime. He would eventually plead guilty to more than a dozen charges stemming from the murder, sexual assault and kidnapping of Jessica, as well as a separate attack on another woman months earlier.

Sigg’s story –– told to CNN and shared here for the first time publicly –– highlights the quandary faced by parents whose children carry out or are suspected of committing high-profile, violent crimes.

Recent examples include that of Charlie Kirk’s alleged shooter, whose father recognized his son in images released by authorities and urged him to turn himself in, and a mother who called police after fearing her son was responsible for an alleged arson at a Florida synagogue days before Rosh Hashanah.

A Westminster Police Officer is surrounded by police vehicles at the Siggs' home, where investigators spent the day gathering evidence in Westminster, Colorado, on October 25, 2012. Ed Andrieski/AP

Sigg’s experience also offers a glimpse at the road families like hers face in the wake of a loved one’s monstrous act: She’s struggled for years with her mental health, describing a near-debilitating remorse, even as the intense public focus on her son and his crime