A 20-year-old Rochester mother has begun serving a work-release sentence for failing to report an incident in which her boyfriend shook her baby daughter in Tumwater, court papers state.

Kati Bergman, 20, reported to Thurston County Jail on Thursday to begin her 90-day sentence after pleading guilty to a count of first-degree criminal mistreatment, domestic violence, as part of a plea agreement in November.

After Bergman failed to report one incident in which her 12-week-old baby girl was shaken, the infant was shaken again by her boyfriend in September, and the child suffered a skull fracture and a rib fracture, court papers state. Bergman is not alleged to have been present.

Jeremy Pawloski, The Olympian