SACRAMENTO, Calif. (CBS13/AP) — A Northern California mother and her boyfriend have been convicted of murdering a 5-year-old boy after inflicting “extensive abuse” on the child.

The boy’s mother, Jessica Prater, 37, and her boyfriend Adam Caldwell, 45, were found guilty on several counts related to the 2016 death of Prater’s son, Zachary Prater-Stokes.

READ MORE: Folsom Ice Skating Rink Reopens After Weeks Of Delays

The mother and child had moved into Caldwell’s home in the Sacramento suburb of Orangevale in April 2016, the district attorney’s office said in a statement.

Zachary Prater-Stokes (credit: Tiffany Guzman)

“Caldwell began to punish and abuse Zachary, both psychologically and physically,” the statement said. “The physical abuse became more frequent and more violent. The abuse was also inflicted by Prater.”

Roughly two months after moving in with her boyfriend, Prater called 911 “to report that Zachary had swallowed water in the bathtub and was not responsive.”

Fire personnel arrived and found Zachary clothed and dry in a bedroom, and transported him to a hospital where he never regained consciousness.

READ MORE: 'AMEND Changed My Life': Program For African American Students Offers Path To Success

Jessica Prater (left) and Adam Caldwell’s (right) booking photos. (Credit: Sacramento County Sheriff’s Department)

“Medical evidence confirmed extensive abuse,” the statement said. The autopsy showed Zachary’s death was caused by “blunt force injuries and water submersion.”

Both defendants’ cases involved nearly three years of pretrial conferences and hearings, with trial proceedings then interrupted in March 2020 by COVID-19 protocols imposed at Sacramento Superior County Court, court records show.

Prater was convicted Friday of first-degree murder by torture, child assault causing death and child abuse with great bodily injury causing death, the district attorney’s office said.

Caldwell was convicted last month of second-degree murder and child assault causing death.

Each faces 25 years to life in prison. Caldwell is scheduled for sentencing Nov. 19. Prater’s sentencing is set for Dec. 10.

MORE NEWS: Rancho Cordova Jumpstarts Job Seeking Programs To Find People High-Paying Jobs

(© Copyright 2021 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)